KR20210043550A - Triarylamine compound, light-emitting element, light-emitting device, electronic device, and lighting device - Google Patents

Abstract

The present invention relates to a triarylamine compound, a light emitting element, a light emitting device, an electronic device, and a lighting device. The novel triarylamine compound having bipolar properties is provided. Furthermore, the light emitting element with high luminous efficiency, the light emitting device having low power consumption, the electronic device, or the lighting device is provided. The triarylamine compound is a triarylamine compound represented by formula G1. According to the present invention, the light emitting element with high luminous efficiency can be provided.

Description

Triarylamine compound, light emitting device, light emitting device, electronic device, and lighting device {TRIARYLAMINE COMPOUND, LIGHT-EMITTING ELEMENT, LIGHT-EMITTING DEVICE, ELECTRONIC DEVICE, AND LIGHTING DEVICE}

One aspect of the present invention relates to a triarylamine compound. Further, it relates to a light-emitting element, a light-emitting device, an electronic device, and a lighting device using a triarylamine compound.

In recent years, research and development of light emitting devices using electroluminescence has been actively conducted. The basic configuration of these light-emitting elements is that a layer containing a light-emitting material is interposed between a pair of electrodes. By applying a voltage to this device, light emission from the luminescent material can be obtained.

Since such a light-emitting element is a self-luminous type, it is considered to be suitable as a flat panel display element because it has advantages such as higher pixel visibility and no backlight compared to a liquid crystal display. . In addition, it is also a great advantage that such a light-emitting element can be manufactured in a thin and lightweight manner. Also, one of the features is that the response speed is very fast.

In addition, since these light-emitting elements can be formed in a film shape, light emission in a planar shape can be easily obtained. Therefore, it is possible to form a large-area device using surface-shaped light emission. Since this is a characteristic that is difficult to obtain in a point light source represented by an incandescent light bulb or an LED, or a line light source represented by a fluorescent lamp, the use value as a surface light source that can be applied to lighting or the like is also high.

Light-emitting elements using the electroluminescence can be roughly classified by whether the light-emitting material is an organic compound or an inorganic compound. When an organic compound is used for the light-emitting material, a pair of electrodes is applied by applying a voltage to the light-emitting element. From, electrons and holes are injected into the layer containing the light-emitting organic compound, respectively, so that a current flows. Then, the luminescent organic compound forms an excited state by these carriers (electrons and holes), and emits light when the excited state returns to the ground state.

From this mechanism, this light-emitting element is called a current-excited light-emitting element. In addition, as the type of the excited state formed by the organic compound, a singlet excited state and a triplet excited state are possible. Light emission from a singlet excited state is called fluorescence, and light emission from a triplet excited state is called phosphorescence.

With regard to such a light-emitting device, there are many problems depending on the material in improving the device characteristics, and in order to overcome these, improvement of the device structure and development of materials have been carried out (for example, Patent Document 1).

Japanese Laid-Open Patent Publication No. 2003-267972

In one aspect of the present invention, a novel triarylamine compound having both hole-transporting properties and electron-transporting properties and having so-called bipolar properties is provided. In addition, one embodiment of the present invention provides a light emitting device having high luminous efficiency. Further, a light emitting device, an electronic device, or a lighting device having low power consumption is provided.

One aspect of the present invention is a triarylamine compound. Accordingly, the constitution of the present invention is a triarylamine compound (G1) represented by the following formula (1).

In Formula 1,

E ¹ is an oxygen or nitrogen atom, and in the case of a nitrogen atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group is bonded,

α ¹ to α ³ are each independently a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, m and n are each independently 0 or 1,

Ar ¹ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazolyl group, a substituted or Any one of an unsubstituted dibenzothiophenyl group, a substituted or unsubstituted dibenzofuranyl group, or an aryl group represented by the following formula (2),

Ar ² is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted It is any one of a substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group,

R ¹ to R ⁴ are either a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

In Chemical Formula 2,

E ² is an oxygen or nitrogen atom, and in the case of a nitrogen atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group is bonded,

α ⁴ to α ⁶ are each independently a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, q is 0 or 1,

Ar ³ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted It is any one of a substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group,

R ⁵ to R ⁸ are either a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

In addition, another aspect of the present invention is a triarylamine compound (G2) represented by the following formula (3).

In Chemical Formula 3,

E ¹ is an oxygen or nitrogen atom, and in the case of a nitrogen atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group is bonded,

α ¹ is any one of a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, m and n are each independently 0 or 1,

Ar ¹ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazolyl group, a substituted or Any one of an unsubstituted dibenzothiophenyl group, a substituted or unsubstituted dibenzofuranyl group, or an aryl group represented by the following formula (4),

Ar ² is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted It is any one of a substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group,

R ¹ to R ⁴ are either a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

In Chemical Formula 4,

E ² is an oxygen or nitrogen atom, and in the case of a nitrogen atom, a substituted or unsubstituted phenyl group or a substituted or unsubstituted biphenyl group is bonded,

α ⁴ is any one of a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, and q is 0 or 1,

Ar ³ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted It is any one of a substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group,

R ⁵ to R ⁸ are either a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

In addition, another aspect of the present invention is a triarylamine compound (G3) represented by the following formula (5).

In Chemical Formula 5,

E ¹ is an oxygen or nitrogen atom, and in the case of a nitrogen atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group is bonded,

m and n are each independently 0 or 1,

Ar ¹ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazolyl group, a substituted or Any one of an unsubstituted dibenzothiophenyl group, a substituted or unsubstituted dibenzofuranyl group, or an aryl group represented by the following formula (6),

Ar ² is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted It is any one of a substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group,

R ¹ to R ⁴ are either a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

In Chemical Formula 6,

E ² is an oxygen or nitrogen atom, and in the case of a nitrogen atom, a substituted or unsubstituted phenyl group or a substituted or unsubstituted biphenyl group is bonded,

q is 0 or 1,

Ar ³ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted It is any one of a substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group,

R ⁵ to R ⁸ are either a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

In addition, another aspect of the present invention is a triarylamine compound represented by the following structural formula (100).

(100)

In addition, another aspect of the present invention is a triarylamine compound represented by the following structural formula (135).

(135)

Further, the triarylamine compound of the present invention has a so-called bipolar property having both hole-transporting properties and electron-transporting properties. In addition, it is characterized by good thermal properties and high amorphous properties. Therefore, it can be applied to a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer of a light emitting device. In addition, since the triarylamine compound of the present invention has a structure constituting an amine via a structure containing a phenyl group bonded to a 5-membered ring, the expansion of conjugation to other heterocycles bonded to the amine can be suppressed. have. For this reason, when the light-emitting layer is formed by a combination of a host material and a guest material (light-emitting material), it can also be used as a host material for a light-emitting material having a relatively short wavelength. Further, since the triarylamine compound of the present invention has fluorescence, it can also be used as a light-emitting substance in a light-emitting layer. Therefore, it is assumed that the present invention also includes a light-emitting device using the triarylamine compound, which is one embodiment of the present invention.

That is, another configuration of the present invention is a light-emitting device having an EL layer between a pair of electrodes, wherein at least one of the light-emitting layer or hole transport layer included in the EL layer contains a triarylamine compound of one embodiment of the present invention. It is characterized.

In addition, one embodiment of the present invention includes not only a light-emitting device having a light-emitting element, but also an electronic device and a lighting device having a light-emitting device in the category. Therefore, the light-emitting device in this specification refers to an image display device, a light-emitting device, or a light source (including a lighting device). In addition, a connector in the light emitting device, for example, a module in which a flexible printed circuit (FPC) or a tape automated bonding (TAB) tape or a tape carrier package (TCP) is mounted, a module in which a printed wiring board is formed at the tip of a TAB tape or TCP, or All modules in which an IC (integrated circuit) is directly mounted on a light emitting device by a chip on glass (COG) method are also included in the light emitting device.

Since the triarylamine compound of one embodiment of the present invention exhibits bipolarity, it can be used for a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer constituting the EL layer of a light emitting device. In addition, by forming a light emitting device by using a triarylamine compound, which is an embodiment of the present invention, for a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, or the like, a light emitting device having high luminous efficiency can be formed. In addition, by applying such a light-emitting element, a light-emitting device, an electronic device, and a lighting device having low power consumption and low driving voltage can be provided.

1 is a diagram explaining the structure of a light-emitting element.
Fig. 2 is a diagram explaining the structure of a light-emitting element.
3A and 3B are diagrams for explaining the structure of a light-emitting element.
Fig. 4 is a diagram explaining a light emitting device.
5A and 5B are diagrams for explaining a light emitting device.
6A to 6D are diagrams for explaining an electronic device.
Fig. 7 is a diagram explaining a lighting fixture.
^{8A and 8B are 1} H-NMR charts of a triarylamine compound represented by structural formula (100).
9A and 9B are ultraviolet and visible absorption spectra and emission spectra of a triarylamine compound represented by structural formula (100).
^{10A and 10B are 1} H-NMR charts of a triarylamine compound represented by structural formula (135).
11A and 11B are ultraviolet and visible absorption spectra and emission spectra of a triarylamine compound represented by structural formula (135).
Fig. 12 is a diagram explaining a light-emitting element.
13 is a diagram showing current density-luminance characteristics of Light-Emitting Element 1. FIG.
14 is a diagram showing voltage-luminance characteristics of Light-Emitting Element 1. FIG.
15 is a diagram showing luminance-current efficiency characteristics of Light-Emitting Element 1. FIG.
16 is a diagram showing voltage-current characteristics of Light-Emitting Element 1. FIG.
17 is a diagram showing luminance-chromaticity characteristics of Light-Emitting Element 1. FIG.
18 is a diagram showing an emission spectrum of Light-Emitting Element 1. FIG.
19 is a diagram showing the reliability of Light-Emitting Element 1;
Fig. 20 is a diagram showing current density-luminance characteristics of Light-Emitting Elements 2 to 4;
Fig. 21 is a diagram showing voltage-luminance characteristics of Light-Emitting Elements 2 to 4;
22 is a diagram showing luminance-current efficiency characteristics of Light-Emitting Elements 2 to 4;
23 is a diagram showing voltage-current characteristics of light-emitting elements 2 to 4;
Fig. 24 is a diagram showing emission spectra of Light-Emitting Elements 2 to 4;
Fig. 25 is a diagram showing current density-luminance characteristics of Light-Emitting Element 5.
26 is a diagram showing voltage-luminance characteristics of Light-Emitting Element 5. FIG.
Fig. 27 is a diagram showing luminance-current efficiency characteristics of Light-Emitting Element 5.
28 is a diagram showing voltage-current characteristics of Light-Emitting Element 5. FIG.
29 is a diagram showing an emission spectrum of Light-Emitting Element 5. FIG.
Fig. 30 is a diagram showing the reliability of Light-Emitting Element 5.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it is possible to variously change the form and details without departing from the spirit and scope of the present invention. Therefore, the present invention is not interpreted as being limited to the description of the embodiments shown below.

(Embodiment 1)

In this embodiment, a triarylamine compound which is one embodiment of the present invention will be described.

The triarylamine compound, which is one embodiment of the present invention, is represented by the following formula (1).

Formula 1

In Formula 1,

E ¹ is an oxygen or nitrogen atom, and in the case of a nitrogen atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group is bonded,

α ¹ to α ³ are each independently a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, m and n are each independently 0 or 1,

Ar ¹ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazolyl group, a substituted or Any one of an unsubstituted dibenzothiophenyl group, a substituted or unsubstituted dibenzofuranyl group, or an aryl group represented by the following formula (2),

Ar ² is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted It is any one of a substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group,

R ¹ to R ⁴ are either a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

Formula 2

In Chemical Formula 2,

E ² is an oxygen or nitrogen atom, and in the case of a nitrogen atom, a substituted or unsubstituted phenyl group or a substituted or unsubstituted biphenyl group is bonded,

α ⁴ to α ⁶ are each independently a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, q is 0 or 1,

Ar ³ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted It is any one of a substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group,

R ⁵ to R ⁸ are either a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

Further, the triarylamine compound represented by the general formula (1) preferably has a molecular weight of 430 or more from the viewpoint of heat resistance of an organic EL device. Further, in the case of forming by a vapor deposition film, a molecular weight of 1000 or less is preferable from the viewpoint of sublimation. More preferably, the molecular weight is 500 or more and 800 or less.

Accordingly, in the triarylamine compound represented by Formula 1, when E ^{1 is a nitrogen atom, Ar 1} is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted tree from the viewpoint of molecular weight. Any one of a phenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group is preferred. .

^{Here, as a specific example of a phenylene group represented by α 1} to α ⁶ or a biphenylene group in Formula 1 or 2, any one of the following structural formulas (s-1) to (s-8) can be mentioned.

Among the structural formulas, the ones that are bonded at the meta position or ortho position as in (s-2), (s-3), (s-5) to (s-8) are preferred because the conjugate is difficult to stretch. It is preferable to bond at the para position as in (s-1) and (s-4) because it can be expected that carrier transportability improves and reliability improves.

^{In addition, as a specific example of Ar 1} to Ar ³ in Formula 1, any one of the following structural formulas (s-11) to (s-25) can be mentioned.

In the above structural formula, since the substituents represented by (s-11) to (s-25) are substituents having a wide band gap, conjugation is difficult to increase, and thus, it is preferable. As shown in (s-12) to (s-25), an aryl group having a ring composed of two or more rings is preferable because of its good carrier transportability. As in (s-19) to (s-22), a 9-position or 3-position-substituted carbazolyl group, a 2-position-substituted dibenzothiophenyl group, or a dibenzofuranyl group is preferable because the hole transport property is improved.

In addition, a triarylamine compound, which is one embodiment of the present invention, is represented by the following formula (3).

Formula 3

In Chemical Formula 3,

E ¹ is an oxygen or nitrogen atom, and in the case of a nitrogen atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group is bonded,

α ¹ is any one of a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, m and n are each independently 0 or 1,

Ar ¹ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazolyl group, a substituted or Any one of an unsubstituted dibenzothiophenyl group, a substituted or unsubstituted dibenzofuranyl group, or an aryl group represented by the following formula (4),

Ar ² is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted It is any one of a substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group,

R ¹ to R ⁴ are either a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

Formula 4

In Chemical Formula 4,

E ² is an oxygen or nitrogen atom, and in the case of a nitrogen atom, a substituted or unsubstituted phenyl group or a substituted or unsubstituted biphenyl group is bonded,

α ⁴ is any one of a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, and q is 0 or 1,

Ar ³ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted It is any one of a substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group,

R ⁵ to R ⁸ are either a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

^{Here, specific examples of α 1} , α ⁴ , Ar ¹ , Ar ² , and Ar ³ in Formula 3 or Formula 4 include the same as those of Formula 1.

In addition, the triarylamine compound, which is one embodiment of the present invention, is represented by the following formula (5).

Formula 5

In Chemical Formula 5,

E ¹ is an oxygen or nitrogen atom, and in the case of a nitrogen atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group is bonded,

m and n are each independently 0 or 1,

Ar ¹ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazolyl group, a substituted or Any one of an unsubstituted dibenzothiophenyl group, a substituted or unsubstituted dibenzofuranyl group, or an aryl group represented by the following formula (6),

Ar ² is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted It is any one of a substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group,

R ¹ to R ⁴ are either a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

Formula 6

In Chemical Formula 6,

E ² is an oxygen or nitrogen atom, and in the case of a nitrogen atom, a substituted or unsubstituted phenyl group or a substituted or unsubstituted biphenyl group is bonded,

q is 0 or 1,

Ar ³ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted It is any one of a substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group,

R ⁵ to R ⁸ are either a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

^{Here, as a specific example of Ar 1} , Ar ² , and Ar ³ in Formula 5 or Formula 6, the same thing as Formula 1 may be mentioned.

In addition, in the triarylamine compound represented by Formulas 1, 3 and 5, having a substituent is preferable because it improves thermal properties (Tg). Specifically, a C1-C6 alkyl group, such as a methyl group, an ethyl group, and a tert-butyl group, a phenyl group, etc. are mentioned.

Next, the specific structural formula of the triarylamine compound which is one embodiment of the present invention described above is shown (the following structural formulas (100) to (118), (130) to (136)). However, the present invention is not limited to these.

In addition, the triarylamine compounds represented by the structural formulas (100) to (118) and (130) to (136) are novel materials having excellent bipolar properties. Specifically, a benzimidazolyl group or a benzoxazolyl group is a skeleton having excellent electron transport properties, and a triarylamine skeleton is a skeleton having excellent hole transport properties.

Next, as an example of a method for synthesizing a triarylamine compound according to an embodiment of the present invention, a method for synthesizing a triarylamine compound represented by Formula 1 will be described.

《Synthesis method of triarylamine compound represented by formula 1》

An example of a method for synthesizing the triarylamine compound represented by the following formula (1) will be described.

Formula 1

The triarylamine compound represented by the general formula (1) can be synthesized by a synthesis method shown in the synthesis scheme represented by Scheme A below.

Scheme A

In the above reaction formula A, X ¹ represents halogen, and the reactivity becomes good in the order of iodine, bromine, and chlorine, which is preferable.

As shown in Scheme A, by coupling a diarylamine compound (a1) and a halogenated aryl compound (a2), a triarylamine compound represented by the above formula (1) is obtained.

In addition, the reaction of Scheme A has various reaction conditions, but as an example, a synthesis method using a metal catalyst in the presence of a base can be applied.

In the above synthesis reaction, a case where the Hartwig-Buchwald reaction is used is described. A palladium catalyst can be used as the metal catalyst, and a mixture of a palladium complex and its ligand can be used as the palladium catalyst. Examples of the palladium complex include bis(dibenzylideneacetone)palladium(0), palladium(II) acetate, and the like. In addition, as the ligand, tri(tert-butyl)phosphine, tri(n-hexyl)phosphine, tricyclohexylphosphine, 1,1-bis(diphenylphosphino)ferrocene (abbreviation: DPPF), etc. Can be mentioned. Moreover, as a substance which can be used as a base, organic bases, such as sodium tert-butoxide, and inorganic bases, such as potassium carbonate, etc. are mentioned. In addition, the reaction is preferably carried out in a solution, and examples of the solvent that can be used include toluene, xylene, benzene, and the like. However, the catalyst that can be used and its ligands, bases, and solvents are not limited thereto. In addition, the reaction is preferably carried out in an inert atmosphere such as nitrogen or argon.

^{In addition, when Ar 1} of the triarylamine compound represented by Formula 1 is Formula 2, the triarylamine compound represented by Formula G'can be synthesized by a synthetic method shown in the synthesis scheme represented by Scheme B below. .

Scheme B

In the above reaction formula B, X ¹ and X ² each independently represent a halogen, and the reactivity of iodine, bromine, and chlorine in the order of iodine, bromine, and chlorine becomes good, which is preferable.

As shown in Scheme B, by coupling a diarylamine compound (a1), a dihalogenated aryl compound (a3), and a diarylamine compound (a4), a triarylamine compound represented by the above formula G1' is obtained. Lose.

In addition, although the reaction of Scheme B has various reaction conditions, as an example, a synthesis method using a metal catalyst in the presence of a base can be applied.

In the above synthesis reaction, a case where the Hartwig-Buchwald reaction is used is described. A palladium catalyst can be used as the metal catalyst, and a mixture of a palladium complex and its ligand can be used as the palladium catalyst. Examples of the palladium complex include bis(dibenzylideneacetone)palladium(0), palladium(II) acetate, and the like. In addition, as the ligand, tri(tert-butyl)phosphine, tri(n-hexyl)phosphine, tricyclohexylphosphine, 1,1-bis(diphenylphosphino)ferrocene (abbreviation: DPPF), etc. Can be mentioned. Moreover, as a substance which can be used as a base, organic bases, such as sodium tert-butoxide, and inorganic bases, such as potassium carbonate, etc. are mentioned. In addition, the reaction is preferably carried out in a solution, and examples of the solvent that can be used include toluene, xylene, benzene, and the like. However, the catalyst that can be used and its ligands, bases, and solvents are not limited thereto. In addition, the reaction is preferably carried out in an inert atmosphere such as nitrogen or argon.

In addition, in this case, it is preferable that the compound (a1) and the compound (a4) are the same, because synthesis becomes simpler.

As described above, an example of a method for synthesizing the triarylamine compound, which is one embodiment of the present invention, has been described, but the present invention is not limited to this, and may be synthesized by any other synthesis method.

Since the triarylamine compound which is one embodiment of the present invention described above is excellent in bipolar properties, it can be used as a carrier transporting material in a light emitting device. In addition, it can also be used as a host material for a light-emitting layer in a light-emitting element.

Further, by using the triarylamine compound as an embodiment of the present invention, a light emitting device having high luminous efficiency and suppressing the increase in driving voltage to a minimum can be realized. Further, by applying such a light-emitting element, a light-emitting device, an electronic device, or a lighting device with low power consumption can be realized.

Moreover, the triarylamine compound which is one embodiment of this invention can also be used for an organic thin film solar cell. Specifically, it can be used for a carrier transport layer and a carrier injection layer of an organic thin film solar cell. Further, it can be used for a charge generation layer by mixing with an acceptor substance. In addition, since it is photo-excited, it can be used as a power generation layer.

The configuration shown in this embodiment can be used in appropriate combination with the configuration shown in the other embodiments.

(Embodiment 2)

In this embodiment, a light-emitting device in which the triarylamine compound shown in Embodiment 1 is used for the hole transport layer is described as an embodiment of the present invention with reference to FIG. 1.

The light-emitting element shown in this embodiment includes a light-emitting layer 113 between a pair of electrodes (first electrode (anode) 101 and second electrode (cathode) 103, as shown in FIG. 1 The EL layer 102 is interposed, and the EL layer 102 includes, in addition to the light emitting layer 113, a hole (or hole) injection layer 111, a hole (or hole) transport layer 112, and an electron transport layer ( 114), an electron injection layer 115, a charge generation layer (E) 116, and the like.

By applying a voltage to such a light emitting element, holes injected from the first electrode 101 and electrons injected from the second electrode 103 are recombined in the light emitting layer 113 to be included in the light emitting layer 113. Put the material into an excited state. And, when the substance in the excited state returns to the ground state, it emits light.

In addition, the hole injection layer 111 in the EL layer 102 is a layer containing a material having high hole transport properties and an acceptor material, and electrons are extracted from the material having high hole transport properties by the acceptor material. Holes (holes) occur. Accordingly, holes are injected into the light emitting layer 113 from the hole injection layer 111 through the hole transport layer 112.

In addition, the charge generation layer (E) 116 is a layer containing a material having high hole transport properties and an acceptor material. Since electrons are extracted from the material having high hole transport properties by the acceptor material, the extracted electrons are injected from the electron injection layer 115 having electron injection properties through the electron transport layer 114 to the light emitting layer 113 .

Hereinafter, a specific example in manufacturing the light emitting device according to the present embodiment will be described.

For the first electrode (anode) 101 and the second electrode (cathode) 103, a metal, an alloy, an electrically conductive compound, a mixture thereof, or the like can be used. Specifically, indium oxide-tin oxide, indium oxide-tin oxide containing silicon or silicon oxide, indium oxide-zinc oxide, indium oxide containing tungsten oxide and zinc oxide, Gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), In addition to titanium (Ti), elements belonging to Group 1 or Group 2 of the periodic table, that is, alkali metals such as lithium (Li) or cesium (Cs), and magnesium (Mg), calcium (Ca), and strontium (Sr) Alkaline earth metals such as, and rare earth metals such as alloys (MgAg, AlLi), europium (Eu), ytterbium (Yb) and the like, alloys containing these, and other graphene may be used. Further, the first electrode (anode) 101 and the second electrode (cathode) 103 can be formed by, for example, a sputtering method or a vapor deposition method (including a vacuum vapor deposition method).

As a material having high hole transport properties used for the hole injection layer 111, the hole transport layer 112, and the charge generation layer (E) 116, for example, 4,4'-bis[N-(1-naph) Tyl)-N-phenylamino]biphenyl (abbreviation: NPB or α-NPD) or N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]- 4,4'-diamine (abbreviation: TPD), 4,4',4''-tris (carbazol-9-yl) triphenylamine (abbreviation: TCTA), 4,4',4''-tris ( N,N-diphenylamino)triphenylamine (abbreviation: TDATA), 4,4',4''-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviation: MTDATA), Aromatic amine compounds such as 4,4'-bis[N-(spiro-9,9'-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB), 3-[N-( 9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazol-3-yl)-N- Phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation : PCzPCN1) etc. are mentioned. In addition, 4,4'-di(N-carbazolyl)biphenyl (abbreviation: CBP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), Carbazole compounds, such as 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA), etc. can be used. The substances described here are mainly ^{substances having a hole mobility of 10 -6} cm 2 /Vs or more. However, as long as it is a material having a higher hole transport property than electrons, a material other than these may be used.

In addition, poly(N-vinylcarbazole) (abbreviation: PVK), poly(4-vinyltriphenylamine) (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenyl) Amino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide] (abbreviation: PTPDMA), poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] High molecular compounds, such as (abbreviation: Poly-TPD), can also be used.

Further, as a substance having high hole transport properties, a triarylamine compound which is one embodiment of the present invention can also be used.

In addition, as the acceptor material used for the hole injection layer 111 and the charge generation layer (E) 116, a transition metal oxide or an oxide of a metal belonging to groups 4 to 8 in the periodic table of elements is used. Can be lifted. Specifically, molybdenum oxide is particularly preferred.

In particular, the triarylamine compound of one embodiment of the present invention is bipolar, and can be suitably used for the hole injection layer 111 and the charge generation layer (E) 116 as a mixture with these acceptor materials. In addition to the above, a bipolar organic compound obtained by combining an electron transport skeleton and a hole transport skeleton can also be used as a mixture with these acceptor substances.

The light-emitting layer 113 is a layer containing a light-emitting material. The light-emitting layer 113 may be composed of only a light-emitting material, or may be composed of a state in which the light-emitting center material is dispersed in a host material.

In the light-emitting layer 113, there is no particular limitation on the material that can be used as the light-emitting material and the light-emitting central material, and the light emitted by these materials may be fluorescence or phosphorescence. Further, examples of the light-emitting material and the light-emitting central material include the following.

As a substance emitting fluorescence, N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N'-diphenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazol-9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), 4-(9H-carbazol-9-yl)-4' -(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H- Carbazol-3-amine (abbreviation: PCAPA), perylene, 2,5,8,11-tetra-tert-butylperylene (abbreviation: TBP), 4-(10-phenyl-9-anthryl)-4 '-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA), N,N''-(2-tert-butylanthracene-9,10-diyldi-4,1- Phenylene)bis[N,N',N'-triphenyl-1,4-phenylenediamine] (abbreviation: DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl-) 2-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N' -Triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA), N,N,N',N',N'',N'',N''',N'''-octaphenyldibenzo[ g,p]Chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), Coumarin 30, N-(9,10-diphenyl-2-anthryl)-N,9-diphenyl-9H -Carbazol-3-amine (abbreviation: 2PCAPA), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H- Carbazol-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA ), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation : 2DPABPhA), 9,10-bis(1,1'-biphenyl-2-yl)-N-[4-(9H-carbazol-9-yl)phenyl]-N-phenylanthracene-2-amine ( Abbreviation: 2YGABPhA), N,N,9-triphenylanthracene-9-amine (abbreviation: DPhAPhA), Coumarin 545T, N,N'-diphenylquinacridone (abbreviation: DPQ d), rubrene, 5,12-bis(1,1'-biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), 2-(2-{2-[4- (Dimethylamino)phenyl]ethenyl}-6-methyl-4H-pyran-4-ylidene)propanedinitrile (abbreviation: DCM1), 2-{2-methyl-6-[2-(2,3,6) ,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCM2), N,N,N' ,N'-tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N'-tetrakis(4-methylphenyl) )Acenaphtho[1,2-a]fluoranthene-3,10-diamine (abbreviation: p-mPhAFD), 2-{2-isopropyl-6-[2-(1,1,7,7-) Tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTI ), 2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizine -9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2,6-bis{2-[4-(dimethylamino)phenyl]ethenyl} -4H-pyran-4-ylidene)propanedinitrile (abbreviation: BisDCM), 2-(2,6-bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3) ,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDCJTM), and the like. .

Further, as a substance emitting fluorescence, a triarylamine compound, which is one embodiment of the present invention, can also be used.

As a substance emitting phosphorescence, bis[2-(3',5'-bistrifluoromethylphenyl)pyridinato-N,C2 ^' ]iridium(III)picolinate (abbreviation: Ir(CF ₃ ppy) ₂ (pic)), bis[2-(4',6'-difluorophenyl ^{)pyridinato-N,C 2'} ]iridium(III)acetylacetonate (abbreviation: FIracac), tris(2-phenylpyri) Dinato) iridium (III) (abbreviation: Ir (ppy) ₃ ), bis (2-phenylpyridinato) iridium (III) acetylacetonate (abbreviation: Ir (ppy) ₂ (acac)), tris (acetylaceto) NATO) (monophenanthroline) terbium (III) (abbreviation: Tb (acac) ₃ (Phen)), bis (benzo [h] quinolinato) iridium (III) acetylacetonate (abbreviation: Ir (bzq) ₂ (acac)), bis(2,4-diphenyl-1,3-oxazolato-N,C ^2' ) iridium(III)acetylacetonate (abbreviation: Ir(dpo) ₂ (acac)), bis[ 2-(4'-perfluorophenylphenyl)pyridinato]iridium(III)acetylacetonate (abbreviation: Ir(p-PF-ph) ₂ (acac)), bis(2-phenylbenzothiazolato- N,C ^2' )Iridium(III)acetylacetonate (abbreviation: Ir(bt) ₂ (acac)), bis[2-(2'-benzo[4,5-α]thienyl)pyridinato-N ,C ^3' ]Iridium(III)acetylacetonate (abbreviation: Ir(btp) ₂ (acac)), bis(1-phenylisoquinolinato-N,C ^2' ) iridium(III)acetylacetonate (abbreviation : Ir(piq) ₂ (acac)), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: Ir(Fdpq) ₂ (acac)) , (Acetylacetonato)bis(2,3,5-triphenylpyrazinato)iridium(III) (abbreviation: Ir(tppr) ₂ (acac)), 2,3,7,8,12,13,17 ,18-octaethyl-21H,23H-porphyrin platinum (II) (abbreviation: PtOEP), tris (1,3-diphenyl-1,3-propanedionato) (monophenanthroline) europium (III) (abbreviation : Eu(DBM) ₃ (Phen)), tris[1-(2-tenoyl)-3,3,3-trifluoroacetonato] (monofenane Troline) europium (III) (abbreviation: Eu(TTA) ₃ (Phen)), etc. are mentioned.

In addition, the material that can be used for the host material is not particularly limited, but examples include tris(8-quinolinolato)aluminum(III) (abbreviation: Alq), tris(4-methyl-8-qui Nolinolato) aluminum (lII) (abbreviation: Almq ₃ ), bis (10-hydroxybenzo[h] quinolinato) beryllium (II) (abbreviation: BeBq ₂ ), bis (2-methyl-8-quinoli) Nolato) (4-phenylphenolato) aluminum (III) (abbreviation: BAlq), bis (8-quinolinolato) zinc (II) (abbreviation: Znq), bis (2- (2-benzoxazolyl) Metal complexes such as phenolato]zinc(II) (abbreviation: ZnPBO), bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ), 2-(4-biphenylyl) -5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4- Oxadiazol-2-yl]benzene (abbreviation: OXD-7), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (Abbreviation: TAZ), 2,2',2''-(1,3,5-benzenetriyl) tris (1-phenyl-1H-benzimidazole) (abbreviation: TPBI), vasophenanthroline (abbreviation : Bphen), vasocuproin (abbreviation: BCP), 9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11) Heterocyclic compounds such as 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB or α-NPD), N,N'-bis(3-methylphenyl) -N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4'-bis[N-(spiro-9,9'-biflu And aromatic amine compounds such as oren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB). Further, condensed polycyclic aromatic compounds such as anthracene derivatives, phenanthrene derivatives, pyrene derivatives, chrysene derivatives, and benzo[g,p]chrysene derivatives may be mentioned. Specifically, 9,10-diphenylanthracene (abbreviation: DPAnth), N,N-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: CzA1PA), 4-(10-phenyl-9 -Anthryl)triphenylamine (abbreviation: DPhPA), 4-(9H-carbazol-9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), N, 9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), N,9-diphenyl-N-{4-[ 4-(10-phenyl-9-anthryl)phenyl]phenyl}-9H-carbazol-3-amine (abbreviation: PCAPBA), N,9-diphenyl-N-(9,10-diphenyl-2- Anthryl)-9H-carbazol-3-amine (abbreviation: 2PCAPA), 6,12-dimethoxy-5,11-diphenylchrysene, N,N,N',N',N'',N'',N''',N'''-octaphenyldibenzo[g,p]chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), 9-[4-(10-phenyl- 9-anthryl)phenyl]-9H-carbazole (abbreviation: CzPA), 3,6-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: DPCzPA), 9,10-bis (3,5-diphenylphenyl) anthracene (abbreviation: DPPA), 9,10-di (2-naphthyl) anthracene (abbreviation: DNA), 2-tert-butyl-9, 10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 9,9'-bianthryl (abbreviation: BANT), 9,9'-(stilbene-3,3'-diyl) diphenanthrene (Abbreviation: DPNS), 9,9'-(stilbene-4,4'-diyl) diphenanthrene (abbreviation: DPNS2), 3,3',3''-(benzene-1,3,5-tri 1) Tripyrene (abbreviation: TPB3), etc. are mentioned. Among these and known substances, one or more substances having an energy gap larger than the energy gap of the light-emitting center substance may be selected and used. In the case where the luminescent central substance is a substance that emits phosphorescence, as the host material, a substance having a triplet excitation energy larger than the triplet excitation energy (the energy difference between the ground state and the triplet excited state) of the luminescent central substance may be selected.

Further, as a material that can be used for the host material, a triarylamine compound which is one embodiment of the present invention can also be used. Since the triarylamine compound of one embodiment of the present invention has a high S1 level, it can be used as a host material for a substance emitting fluorescence in a light emitting region in the visible region. Since the triarylamine compound of one embodiment of the present invention has a high T1 level, when used as a host material for a substance that emits phosphorescence, it can be used in a light emitting region having a longer wavelength than green.

Further, the light-emitting layer 113 may have a structure in which two or more layers are stacked. For example, when the light emitting layer 113 is formed by sequentially stacking the first light emitting layer and the second light emitting layer from the side of the hole transport layer, a material having hole transport properties is used as the host material of the first light emitting layer, and the host material of the second light emitting layer There is a configuration in which a material having electron transport properties is used.

The electron transport layer 114 is a layer containing a material having high electron transport properties. In the electron transport layer 114, Alq ₃ , tris (4-methyl-8-quinolinolato) aluminum (abbreviation: Almq ₃ ), bis (10-hydroxybenzo [h] quinolinato) beryllium (abbreviation: BeBq ₂ ), BAlq, Zn(BOX) ₂ , bis[2-(2-hydroxyphenyl)benzothiazolato]zinc (abbreviation: Zn(BTZ) ₂ ), and other metal complexes may be used. Further, 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5-(p-tert -Butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenyl Ryl)-1,2,4-triazole (abbreviation: TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2 ,4-triazole (abbreviation: p-EtTAZ), vasophenanthroline (abbreviation: Bphen), vasocuproin (abbreviation: BCP), 4,4'-bis(5-methylbenzooxazol-2-yl) ) Heteroaromatic compounds such as stilbene (abbreviation: BzOs) can also be used. In addition, poly(2,5-pyridindiyl) (abbreviation: PPy), poly[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridin-3,5-diyl)] (abbreviation : PF-Py), poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridin-6,6'-diyl)] (abbreviation: PF-BPy ) May also be used. The substances described here are mainly ^{substances having an electron mobility of 10 -6} cm 2 /Vs or more. Further, as long as the material has higher electron transport properties than holes, a material other than the above may be used as the electron transport layer.

In addition, the electron transport layer may be not only a single layer, but also a stack of two or more layers made of the above material.

The electron injection layer 115 is a layer containing a material having high electron injection properties. For the electron injection layer 115, an alkali metal such as lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF ₂ ), lithium oxide (LiOx), or a compound thereof may be used. In addition, rare earth metal compounds such as erbium fluoride (ErF _{3) can be used.} In addition, a material constituting the electron transport layer 114 may be used.

Alternatively, a composite material obtained by mixing an organic compound and an electron donor (donor) may be used for the electron injection layer 115. Such a composite material is excellent in electron injection properties and electron transport properties because electrons are generated in the organic compound by the electron donor. In this case, the organic compound is preferably a material having excellent transport of generated electrons, and specifically, for example, a material constituting the electron transport layer 114 (such as a metal complex or a heteroaromatic compound) can be used. . The electron donor may be a substance that exhibits electron donation to an organic compound. Specifically, an alkali metal, alkaline earth metal, or rare earth metal is preferable, and lithium, cesium, magnesium, calcium, erbium, ytterbium, and the like are exemplified. Further, an alkali metal oxide or an alkaline earth metal oxide is preferable, and lithium oxide, calcium oxide, barium oxide and the like are exemplified. It is also possible to use Lewis bases such as magnesium oxide. Further, an organic compound such as tetrathiafulvalene (abbreviation: TTF) can also be used.

In addition, the hole injection layer 111, the hole transport layer 112, the light-emitting layer 113, the electron transport layer 114, the electron injection layer 115, and the charge generation layer (E) 116, respectively, the evaporation method ( It can be formed by a method such as a vacuum evaporation method), an ink jet method, a coating method, or the like.

In the above-described light-emitting element, a current flows due to a potential difference generated between the first electrode 101 and the second electrode 103, and holes and electrons recombine in the EL layer 102 to emit light. Then, this light emission is extracted to the outside through either or both of the first electrode 101 and the second electrode 103. Accordingly, either or both of the first electrode 101 and the second electrode 103 become an electrode having light-transmitting properties.

Since the light-emitting device described above is formed by applying the triarylamine compound, which is one embodiment of the present invention, to the hole transport layer, not only the device efficiency of the light-emitting device is improved, but also the increase in driving voltage can be suppressed to a minimum.

In addition, since the triarylamine compound of one embodiment of the present invention can be used not only in the hole transport layer but also in other layers (hole injection layer, light emitting layer, electron transport layer, etc.), it is preferable to use a common material in a plurality of layers. It becomes possible. For this reason, it is possible to suppress the cost of synthesizing materials and the manufacturing cost of the light emitting element, which is preferable.

In addition, the light-emitting element shown in this embodiment is an example of a light-emitting element manufactured by applying the triarylamine compound, which is one embodiment of the present invention. Further, as a configuration of a light emitting device having the above element structure, a passive matrix type light emitting device or an active matrix type light emitting device can be mentioned. It can also be applied to a light emitting device having a microcavity structure. It is assumed that all of these light emitting devices are included in the present invention. In addition, in these light emitting devices, power consumption can be reduced.

In addition, in the case of an active matrix type light emitting device, the structure of the TFT is not particularly limited. For example, a staggered or inverted staggered TFT can be suitably used. Further, the driving circuit formed on the TFT substrate may be formed of an N-type and P-type TFT, or may be formed of only one of an N-type TFT or a P-type TFT. Further, the crystallinity of the semiconductor film used for the TFT is not particularly limited. For example, an amorphous semiconductor film, a crystalline semiconductor film, and other oxide semiconductor films can be used.

In addition, it is assumed that the configuration shown in the present embodiment can be used in appropriate combination with the configuration shown in the other embodiments.

(Embodiment 3)

In this embodiment, as an embodiment of the present invention, a light-emitting element in which two or more kinds of organic compounds different from the phosphorescent compound are used in the light-emitting layer will be described.

The light-emitting element shown in this embodiment has a structure including an EL layer 203 between a pair of electrodes (anode 201 and cathode 202) as shown in FIG. 2. Further, the EL layer 203 includes at least a light emitting layer 204, and may include a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a charge generation layer (E), or the like. Further, for the hole injection layer, the hole transport layer, the electron transport layer, the electron injection layer, and the charge generation layer (E), the material shown in the second embodiment can be used.

The light emitting layer 204 shown in this embodiment contains a phosphorescent compound 205, a first organic compound 206, and a second organic compound 207. The triarylamine compound shown in Embodiment 1 can be used as the first organic compound 206 or the second organic compound 207. In addition, the phosphorescent compound 205 is a guest material in the light emitting layer 204. In addition, one of the first organic compounds 206 and the second organic compounds 207 in which the ratio contained in the light-emitting layer 204 is larger is used as the host material for the light-emitting layer 204.

In the light-emitting layer 204, by dispersing the guest material in a host material, crystallization of the light-emitting layer can be suppressed. Further, concentration quenching due to a high concentration of the guest material can be suppressed, and the luminous efficiency of the light emitting element can be increased.

In addition, it is preferable that the triplet excitation energy level (T1 level) of each of the first organic compound 206 and the second organic compound 207 is higher than the T1 level of the phosphorescent compound 205. When the T1 level of the first organic compound 206 (or the second organic compound 207) is lower than the T1 level of the phosphorescent compound 205, the triplet excitation energy of the phosphorescent compound 205 that contributes to light emission This is because the first organic compound 206 (or the second organic compound 207) is quenched (quenched) to cause a decrease in luminous efficiency.

Here, in order to increase the efficiency of energy transfer from the host material to the guest material, the Forster mechanism (dipole-dipole interaction) and the Dexter mechanism (electron exchange interaction) known as the intermolecular energy transfer mechanism. Action), the emission spectrum of the host material (fluorescence spectrum when discussing energy transfer from a singlet excited state, phosphorescence spectrum when discussing energy transfer from a triplet excited state) and absorption spectrum of the guest material. (More specifically, it is preferable that the overlap with the spectrum in the absorption band on the longest wavelength (low energy) side) increases. However, it is usually difficult to overlap the fluorescence spectrum of the host material with the absorption spectrum in the absorption band on the longest wavelength (low energy) side of the guest material. This is because, when doing so, the phosphorescent spectrum of the host material is located on the longer wavelength (lower energy) side than the fluorescence spectrum, so the T1 level of the host material is lower than the T1 level of the phosphorescent compound, and the above-described quenching problem occurs. . On the other hand, in order to avoid the problem of quench, if the T1 level of the host material is designed to exceed the T1 level of the phosphorescent compound, this time, the fluorescence spectrum of the host material shifts to the short wavelength (high energy) side, so the fluorescence spectrum is It does not overlap with the absorption spectrum in the absorption band on the longest wavelength (low energy) side of the guest material. Therefore, it is usually difficult to maximize the energy transfer from the singlet excited state of the host material by superimposing the fluorescence spectrum of the host material with the absorption spectrum in the absorption band on the longest wavelength (low energy) side of the guest material.

Therefore, in this embodiment, it is preferable that the 1st organic compound and the 2nd organic compound are a combination which forms an excitation complex (it is also called an exciplex). In this case, upon recombination of carriers (electrons and holes) in the light emitting layer 204, the first organic compound 206 and the second organic compound 207 form an excitation complex. Thereby, in the light emitting layer 204, the fluorescence spectrum of the first organic compound 206 and the fluorescence spectrum of the second organic compound 207 are converted into the emission spectrum of the excitation complex located on the longer wavelength side. And, if the first organic compound and the second organic compound are selected so that the overlap of the emission spectrum of the excitation complex and the absorption spectrum of the guest material increases, the energy transfer from the singlet excited state can be maximized. In addition, in the triplet excited state as well, it is considered that energy transfer from the excitation complex rather than the host material occurs.

As the phosphorescent compound (205), it is preferable to use a phosphorescent organometallic complex. In addition, the first organic compound 206 and the second organic compound 207 may be a combination that generates an excitation complex, but a compound that is easy to receive electrons (electron trapping compound) and a compound that is easy to receive holes (holes It is preferable to combine a trapping compound).

As a phosphorescent organometallic complex, for example, bis[2-(3',5'-bistrifluoromethylphenyl)pyridinato-N,C2 ^' ]iridium(III)picolinate (abbreviation: Ir( CF ₃ ppy) ₂ (pic)), bis[2-(4',6'-difluorophenyl ^{)pyridinato-N,C 2'} ]iridium(III)acetylacetonate (abbreviation: FIracac), tris (2-phenylpyridinato) iridium (III) (abbreviation: Ir (ppy) ₃ ), bis (2-phenylpyridinato) iridium (III) acetylacetonate (abbreviation: Ir (ppy) ₂ (acac)) , Tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviation: Tb(acac) ₃ (Phen)), bis(benzo[h]quinolinato)iridium(III)acetylacetonate (abbreviation: Ir(bzq) ₂ (acac)), bis(2,4-diphenyl-1,3- ^{oxazolato-N,C 2'} ) iridium(III)acetylacetonate (abbreviation: Ir(dpo) ₂ (acac )), bis[2-(4'-perfluorophenylphenyl)pyridinato]iridium(III)acetylacetonate (abbreviation: Ir(p-PF-ph) ₂ (acac)), bis(2-phenyl Benzothiazolato-N,C ^2' )Iridium(III)acetylacetonate (abbreviation: Ir(bt) ₂ (acac)), bis[2-(2'-benzo[4,5-α]thienyl) Pyridinato-N,C ^3' ] iridium (III) acetylacetonate (abbreviation: Ir (btp) ₂ (acac)), bis (1-phenylisoquinolinato-N, C ^2' ) iridium (III) Acetylacetonate (abbreviation: Ir(piq) ₂ (acac)), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: Ir(Fdpq) ₂ (acac)), (acetylacetonato) bis(2,3,5-triphenylpyrazinato) iridium(III) (abbreviation: Ir(tppr) ₂ (acac)), 2,3,7,8, 12,13,17,18-octaethyl-21H,23H-porphyrin platinum (II) (abbreviation: PtOEP), tris (1,3-diphenyl-1,3-propanedionato) (monophenanthroline) europium (III) (abbreviation: Eu(DBM) ₃ (Phen)), tris[1-(2-tenoyl)-3,3,3-trifluoroa Setonato] (monophenanthroline) europium (III) (abbreviation: Eu(TTA) ₃ (Phen)) and the like.

Examples of compounds that are likely to receive electrons include 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[4 -(3,6-diphenyl-9H-carbazol-9-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2CzPDBq-III), 7-[3-(dibenzothiophene-4- Yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 7mDBTPDBq-II), and 6-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation : 6mDBTPDBq-II) is mentioned.

As the compound easily receiving holes, a triarylamine compound which is one embodiment of the present invention can be used. In addition, for example, 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 3-[N-(1-naphthyl)-N -(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1), 4,4',4''-tris[N-(1-naphthyl)-N-phenylamino ]Triphenylamine (abbreviation: 1'-TNATA), 2,7-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-spiro-9,9'-bifluorene (abbreviation: DPA2SF ), N,N'-bis(9-phenylcarbazol-3-yl)-N,N'-diphenylbenzene-1,3-diamine (abbreviation: PCA2B), N-(9,9-dimethyl-2 -N',N'-diphenylamino-9H-fluoren-7-yl)diphenylamine (abbreviation: DPNF), N,N',N''-triphenyl-N,N',N'' tris (9-phenylcarbazol-3-yl)benzene-1,3,5-triamine (abbreviation: PCA3B), 2-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]spiro -9,9'-bifluorene (abbreviation: PCASF), 2-[N-(4-diphenylaminophenyl)-N-phenylamino]spiro-9,9'-bifluorene (abbreviation: DPASF), N,N'-bis[4-(carbazol-9-yl)phenyl]-N,N'-diphenyl-9,9-dimethylfluorene-2,7-diamine (abbreviation: YGA2F), 4,4 '-Bis[N-(3-methylphenyl)-N-phenylamino]biphenyl (abbreviation: TPD), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (Abbreviation: DPAB), N-(9,9-dimethyl-9H-fluoren-2-yl)-N-(9,9-dimethyl-2-[N'-phenyl-N'-(9,9- Dimethyl-9H-fluoren-2-yl)amino]-9H-fluoren-7-yl}phenylamine (abbreviation: DFLADFL), 3-[N-(9-phenylcarbazol-3-yl)-N- Phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3-[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1), 3,6- Bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA2), 4,4'-bis(N-{4-[N'-(3-methylphenyl) )-N'-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviation: DNTPD), 3,6-bis[N-(4-dipe) Nylaminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviation: PCzTPN2), 3,6-bis[N-(9-phenylcarbazol-3-yl)-N-phenyl Amino]-9-phenylcarbazole (abbreviation: PCzPCA2) is mentioned.

The first organic compound 206 and the second organic compound 207 described above are not limited thereto, and are combinations capable of forming an excitation complex, and the emission spectrum of the excitation complex is the absorption of the phosphorescent compound 205 It overlaps with the spectrum, and it is good if the peak of the emission spectrum of the excitation complex is longer than the peak of the absorption spectrum of the phosphorescent compound 205.

In addition, when the first organic compound 206 and the second organic compound 207 are composed of a compound that is easy to receive electrons and a compound that is easy to receive holes, the carrier balance can be controlled by the mixing ratio thereof. Specifically, the range of the first organic compound: the second organic compound = 1:9 to 9:1 is preferable.

The light-emitting element shown in this embodiment can improve the energy transfer efficiency by using energy transfer using the superposition of the emission spectrum of the excitation complex and the absorption spectrum of the phosphorescent compound, so that a light-emitting element with high external quantum efficiency can be realized. I can.

In addition, as another configuration included in the present invention, as the phosphorescent compound 205 (guest material), as other two types of organic compounds, the light emitting layer 204 is formed using a host molecule having a hole trapping property and a host molecule having an electron trapping property. To form the light emitting layer 204 so that holes and electrons are derived from guest molecules present in the two types of host molecules, so that the guest molecules are in an excited state (i.e., Guest Coupled with Complementary Hosts: GCCH). Configuration is also possible.

In this case, as the host molecule of the hole trapping property and the host molecule of the electron trapping property, the above-described compound easily receiving holes and the compound easily receiving electrons can be used, respectively.

In addition, the light-emitting element shown in this embodiment is an example of a light-emitting element manufactured by applying the triarylamine compound, which is one embodiment of the present invention. In addition, as a configuration of a light emitting device having the above element structure, a passive matrix type light emitting device or an active matrix type light emitting device can be exemplified, and by improving part of the element structure, it can be applied to a light emitting device having a microcavity structure May be. It is assumed that all of these light emitting devices are included in the present invention.

In addition, in the case of an active matrix type light emitting device, the structure of the TFT is not particularly limited. For example, a staggered or inverted staggered TFT can be appropriately used. Further, the driving circuit formed on the TFT substrate may be formed of an N-type and P-type TFT, or may be formed of only one of an N-type TFT or a P-type TFT. Further, the crystallinity of the semiconductor film used for the TFT is not particularly limited. For example, an amorphous semiconductor film, a crystalline semiconductor film, and other oxide semiconductor films can be used.

In addition, it is assumed that the configuration shown in the present embodiment can be used in appropriate combination with the configuration shown in the other embodiments.

(Embodiment 4)

In this embodiment, as an embodiment of the present invention, a light-emitting element having a structure having a plurality of EL layers (hereinafter referred to as a tandem light-emitting element) with a plurality of EL layers interposed therebetween will be described.

The light emitting element shown in this embodiment is a plurality of EL layers (first EL layer 302) between a pair of electrodes (first electrode 301 and second electrode 304), as shown in Fig. 3A. ) (1), a tandem type light emitting device having a second EL layer 302 (2).

In this embodiment, the first electrode 301 is an electrode that functions as an anode, and the second electrode 304 is an electrode that functions as a cathode. In addition, the first electrode 301 and the second electrode 304 can use the same configuration as in the second embodiment. In addition, a plurality of EL layers (the first EL layer 302 (1), the second EL layer 302 (2)) may have the same configuration as the EL layer shown in Embodiment 2 or 3, but either The same configuration may be used. That is, the first EL layer 302 (1) and the second EL layer 302 (2) may have the same configuration or different configurations, and the same configuration as in the second embodiment or the third embodiment can be applied. .

Further, a charge generation layer (I) 305 is formed between a plurality of EL layers (first EL layer 302 (1) and second EL layer 302 (2)). When a voltage is applied to the first electrode 301 and the second electrode 304, the charge generation layer (I) 305 injects electrons into one EL layer and injects holes into the other EL layer. It has a function to do. In the case of this embodiment, when a voltage is applied to the first electrode 301 so that the potential becomes higher than that of the second electrode 304, the first EL layer 302 (1) from the charge generation layer (I) 305 Electrons are injected, and holes are injected into the second EL layer 302 (2).

In addition, the charge generation layer (I) 305 has transparency to visible light in terms of light extraction efficiency (specifically, the transmittance of visible light to the charge generation layer (I) 305 is 40% or more. ) Is preferred. In addition, the charge generation layer (I) 305 functions even with a conductivity lower than that of the first electrode 301 or the second electrode 304.

The charge generating layer (I) 305 may have a configuration in which an electron acceptor (acceptor) is added to an organic compound having high hole transport properties, or a configuration in which an electron donor (donor) is added to an organic compound having high electron transport properties. In addition, both configurations may be laminated.

In the case where an electron acceptor is added to an organic compound having high hole transport properties, examples of the organic compound having high hole transport properties include NPB, TPD, TDATA, MTDATA, 4,4'-bis[N-(spiro Aromatic amine compounds, such as -9,9'-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB), and the like can be used. The substances described here are mainly ^{substances having a hole mobility of 10 -6} cm 2 /Vs or more. However, as long as it is an organic compound having higher hole transport properties than electrons, a substance other than the above may be used. Further, the carbazole compound of one embodiment of the present invention can also be used as an organic compound having high hole transport properties in the charge generation layer (I) 305.

Moreover, as an electron acceptor, 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F ₄ -TCNQ), chloranyl, etc. are mentioned. Further, a transition metal oxide can be mentioned. Further, oxides of metals belonging to groups 4 to 8 in the periodic table of the elements may be mentioned. Specifically, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide are preferable because of their high electron acceptability. Among these, molybdenum oxide is particularly preferable because it is stable in the air, has low hygroscopicity, and is easy to handle.

On the other hand, in the case where an electron donor is added to an organic compound having high electron transport properties, examples of the organic compound having high electron transport properties include, for example, a quinoline skeleton or a benzoquinoline skeleton, such as _{Alq, Almq 3} , BeBq _{2, BAlq, etc.} A metal complex or the like can be used. In addition, metal complexes having an oxazole-based and thiazole-based ligand such as Zn(BOX) ₂ and Zn(BTZ) _{2 can also be used.} In addition to the metal complex, PBD, OXD-7, TAZ, Bphen, BCP, and the like can also be used. The substances described here are mainly ^{substances having an electron mobility of 10 -6} cm 2 /Vs or more. Further, as long as it is an organic compound having higher electron transport properties than holes, a substance other than the above may be used.

In addition, as the electron donor, an alkali metal, alkaline earth metal, rare earth metal, or metal belonging to Groups 2 and 13 in the periodic table of elements, and oxides and carbonates thereof can be used. Specifically, it is preferable to use lithium (Li), cesium (Cs), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium oxide, cesium carbonate, and the like. Further, an organic compound such as tetratianapthacene may be used as the electron donor.

Further, by forming the charge generation layer (I) 305 using the above material, it is possible to suppress an increase in the driving voltage when the EL layer is laminated.

In this embodiment, a light-emitting element having two EL layers has been described, but as shown in Fig. 3B, the EL layers 302(1) to 302(n) of n layers (where n is 3 or more) ) Are stacked, and charge generation layers (I) 305(1) to 305(n-1) are disposed between these EL layers 302(1) to 302(n), respectively. It is possible to apply. In the case of having a plurality of EL layers between a pair of electrodes, as in the light emitting device according to the present embodiment, by disposing a charge generation layer (I) between the EL layer and the EL layer, while maintaining a low current density, a high luminance region Light emission from is possible. Since the current density can be kept low, a long life element can be realized. In addition, when lighting is used as an application example, since the voltage drop due to the resistance of the electrode material can be reduced, uniform light emission in a large area becomes possible. In addition, it is possible to realize a light-emitting device with low power consumption by enabling low voltage driving.

Further, by setting the luminous colors of the respective EL layers to be different, light emission of a desired color can be obtained as a whole light-emitting element. For example, in a light-emitting element having two EL layers, it is possible to obtain a light-emitting element that emits white light as the whole light-emitting element by making the light-emitting color of the first EL layer and the light-emitting color of the second EL layer a complementary color. . On the other hand, the complementary color refers to the relationship between colors that become achromatic when mixed. That is, white light emission can be obtained by mixing light obtained from a substance emitting a color having a complementary color relationship.

The same applies to the case of a light-emitting element having three EL layers, for example, when the luminous color of the first EL layer is red, the luminous color of the second EL layer is green, and the luminous color of the third EL layer is blue. , White light emission can be obtained as the whole light-emitting element.

In addition, the configuration shown in this embodiment can be used in appropriate combination with the configuration shown in the other embodiments.

(Embodiment 5)

The light-emitting device according to the present embodiment has a microscopic optical resonator (microcavity) structure utilizing a resonance effect of light between a pair of electrodes, and as shown in FIG. 4, a pair of electrodes (reflective electrode 401) And a plurality of light emitting elements having a structure having at least an EL layer 405 between the semi-reflective electrodes 402). Further, the EL layer 405 may have at least a light emitting layer 404 serving as a light emitting region, and may include a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a charge generation layer (E), or the like. In addition, the triarylamine compound of one embodiment of the present invention can be used for a hole injection layer, a hole transport layer, a light emitting layer 404, or an electron transport layer included in the EL layer 405.

In this embodiment, as shown in Fig. 4, light-emitting elements having different structures (first light-emitting element (R) 410R, second light-emitting element (G) 410G, third light-emitting element (B) 410B) A light-emitting device configured with) will be described.

The first light-emitting element (R) 410R includes a first transparent conductive layer 403a on the reflective electrode 401, a first light-emitting layer (B) 404B, a second light-emitting layer (G) 404G, and a third It has a structure in which an EL layer 405 including a part of the light emitting layer (R) 404R and a transflective/reflective electrode 402 are sequentially stacked. In addition, in the second light emitting element (G) 410G, a second transparent conductive layer 403b, an EL layer 405, and a transflective/reflective electrode 402 are sequentially stacked on the reflective electrode 401. Have a structure. Further, the third light-emitting element (B) 410B has a structure in which an EL layer 405 and a transflective/reflective electrode 402 are sequentially stacked on a reflective electrode 401.

In addition, in the light-emitting element (first light-emitting element (R) 410R, second light-emitting element (G) 410G, and third light-emitting element (B) 410B), a reflective electrode 401, an EL layer 405 and the transflective/reflective electrode 402 are in common. In addition, in the first light-emitting layer (B) 404B, light (λ _B ) having a peak in a wavelength region of 420 nm or more and 480 nm or less is emitted, and in the second light-emitting layer (G) 404G, a wavelength of 500 nm or more and 550 nm or less _{Light (λ G} ) having a peak is emitted in the region, and in the third emission layer (R) 404R, light (λ _R ) having a peak in a wavelength region of 600 nm or more and 760 nm or less is emitted. As a result, in any of the light-emitting elements (the first light-emitting element (R) 410R, the second light-emitting element (G) 410G, and the third light-emitting element (B) 410B), the first light-emitting layer (B) ( Light emission from the 404B), the second emission layer (G) 404G, and the third emission layer (R) 404R overlap, that is, broad light over a visible light region may be emitted. In addition, from the above, it is assumed that _{the length of the wavelength is a relation of λ B} <λ _G <λ _R.

Each light-emitting element shown in this embodiment has a structure formed by interposing an EL layer 405 between a reflective electrode 401 and a semi-transmissive/reflective electrode 402, respectively, and is included in the EL layer 405. Light emission emitted from each light-emitting layer in all directions is resonated by a reflective electrode 401 and a semi-transmissive/reflective electrode 402 that functions as a microscopic light resonator (microcavity). Further, the reflective electrode 401 is formed of a reflective conductive material, and the reflectance of visible light to the film is 40% to 100%, preferably 70% to 100%, and the resistivity is 1×10 ^{Use a} film of less than -2 Ωcm. Further, the semi-transmissive/reflective electrode 402 is formed of a reflective conductive material and a light-transmitting conductive material, and the reflectance of visible light to the film is 20% to 80%, preferably 40% to It is assumed that the film is 70% and the resistivity is 1×10 ^{-2 Ωcm or less.}

In addition, in this embodiment, each light-emitting element is a transparent conductive layer (first transparent conductive layer 403a) formed on each of the first light-emitting element (R) 410R and the second light-emitting element (G) 410G. 2 By changing the thickness of the transparent conductive layer 403b, the optical distance between the reflective electrode 401 and the transflective/reflective electrode 402 for each light emitting element is changed. That is, the broad light emitted from each light-emitting layer of each light-emitting element is between the reflective electrode 401 and the semi-transmissive/reflective electrode 402, reinforcing light with a wavelength that resonates, and light with a wavelength that does not resonate. Since can be attenuated, light of different wavelengths can be extracted by changing the optical distance between the reflective electrode 401 and the transflective/reflective electrode 402 for each element.

Incidentally, the optical distance (also referred to as the optical path length) is a product obtained by multiplying the actual distance by the refractive index, and in this embodiment, the actual film thickness is multiplied by n (refractive index). That is, "optical distance = actual film thickness x n".

In addition, in the first light-emitting element (R) 410R, the total thickness from the reflective electrode 401 to the transflective/reflective electrode 402 is mλ _R /2 (where m is a natural number), and the second light-emitting element In (G) 410G, the total thickness from the reflective electrode 401 to the transflective/reflective electrode 402 is mλ _G /2 (where m is a natural number), and the third light-emitting element (B) 410B In, the total thickness from the reflective electrode 401 to the transflective/reflective electrode 402 is set to mλ _B /2 (where m is a natural number).

From the above, from the first light-emitting element (R) 410R, the light (λ _R ) emitted from the third light-emitting layer (R) 404R mainly included in the EL layer 405 is extracted, and the second light-emitting element _{From (G) 410G, light (λ G} ) emitted from the second light-emitting layer (G) 404G mainly included in the EL layer 405 is extracted, and from the third light-emitting element (B) 410B. _{The light λ S} mainly emitted from the first light-emitting layer (B) 404B included in the EL layer 405 is extracted. Further, the light extracted from each light emitting element is emitted from the transflective/reflective electrode 402 side, respectively.

Further, in the above configuration, the total thickness from the reflective electrode 401 to the transflective/reflective electrode 402 is, strictly, from the reflective region of the reflective electrode 401 to the transflective/reflective electrode 402 It can be said that it is the total thickness up to the reflective area in ). However, since it is difficult to precisely determine the position of the reflective region in the reflective electrode 401 or the transflective/reflective electrode 402, the reflective electrode 401 and the transflective/reflective electrode 402 It is assumed that the above effect can be sufficiently obtained by assuming an arbitrary position as the reflection area.

Next, in the first light-emitting element (R) 410R, the optical distance from the reflective electrode 401 to the third light-emitting layer (R) 404R is set to a desired film thickness ((2m'+1)λ _R /4 (However, m'is a natural number)), the light emission from the third light-emitting layer (R) 404R can be amplified. During light emission from the third light-emitting layer (R) 404R, light reflected by the reflective electrode 401 and returned (first reflected light) is transmitted from the third light-emitting layer (R) 404R to the semi-transmissive/reflective electrode 402 ), the optical distance from the reflective electrode 401 to the third light emitting layer (R) 404R is set to a desired value ((2m'+1)λ _R /4 (However, m'is a natural number)), thereby amplifying light emission from the third emission layer (R) 404R by matching the phases of the first reflected light and the first incident light.

In addition, the optical distance between the reflective electrode 401 and the third light-emitting layer (R) 404R is, strictly, the reflective area in the reflective electrode 401 and the light-emitting area in the third light-emitting layer (R) 404R. It can be called the optical distance of. However, since it is difficult to precisely determine the position of the reflective region in the reflective electrode 401 or the light emitting region in the third light emitting layer (R) 404R, an arbitrary position of the reflective electrode 401 is reflected. It is assumed that the above effect can be sufficiently obtained by assuming an arbitrary position of the region and the third light emitting layer (R) 404R as the light emitting region.

Next, in the second light-emitting element (G) 410G, the optical distance from the reflective electrode 401 to the second light-emitting layer (G) 404G is a desired film thickness ((2m''+1)λ _G / 4 (where m'' is a natural number)), light emission from the second emission layer (G) 404G can be amplified. During light emission from the second light-emitting layer (G) 404G, the light reflected by the reflective electrode 401 and returned (second reflected light) is transmitted from the second light-emitting layer (G) 404G to the semi-transmissive/reflective electrode 402 ), the optical distance from the reflective electrode 401 to the second light emitting layer (G) 404G is set to a desired value ((2m''+1)λ _G / 4 (where m'' is a natural number)), the light emission from the second emission layer (G) 404G may be amplified by matching the phase of the second reflected light and the second incident light.

In addition, the optical distance between the reflective electrode 401 and the second light-emitting layer (G) 404G is, strictly, the reflective area in the reflective electrode 401 and the light-emitting area in the second light-emitting layer (G) 404G. It can be called the optical distance of. However, since it is difficult to precisely determine the position of the reflective region in the reflective electrode 401 or the light emitting region in the second light emitting layer (G) 404G, an arbitrary position of the reflective electrode 401 is reflected. It is assumed that the above effect can be sufficiently obtained by assuming that the region and an arbitrary position of the second light emitting layer (G) 404G are the light emitting region.

Next, in the third light-emitting element (B) 410B, the optical distance from the reflective electrode 401 to the first light-emitting layer (B) 404B is set to a desired film thickness ((2m'''+1)λ _B By adjusting to /4 (where m''' is a natural number)), light emission from the first emission layer (B) 404B can be amplified. During light emission from the first light-emitting layer (B) 404B, the light reflected by the reflective electrode 401 and returned (third reflected light) is transmitted from the first light-emitting layer (B) 404B to the semi-transmissive/reflective electrode 402 ), the optical distance from the reflective electrode 401 to the first light emitting layer (B) 404B is set to a desired value ((2m'''+1)λ _B /4 (where m''' is a natural number)), it is possible to amplify light emission from the first emission layer (B) 404B by matching the phases of the third reflected light and the third incident light.

In addition, in the third light-emitting element, the optical distance between the reflective electrode 401 and the first light-emitting layer (B) 404B is, strictly, the reflective area in the reflective electrode 401 and the first light-emitting layer (B) ( It can be said that it is an optical distance to the light-emitting region in 404B). However, since it is difficult to precisely determine the position of the reflective region in the reflective electrode 401 or the light emitting region in the first light emitting layer (B) 404B, an arbitrary position of the reflective electrode 401 is reflected. It is assumed that the above-described effects can be sufficiently obtained by assuming the region and an arbitrary position of the first light-emitting layer (B) 404B as the light-emitting region.

Further, in the above configuration, any light emitting device has a structure having a plurality of light emitting layers in the EL layer, but the present invention is not limited to this, for example, the configuration of the tandem light emitting device described in Embodiment 4 and In combination, a plurality of EL layers may be formed on one light-emitting element with a charge generation layer interposed therebetween, and a single or a plurality of light-emitting layers may be formed on each of the EL layers.

The light-emitting device shown in the present embodiment has a microcavity structure, and even if it has the same EL layer, light having a different wavelength can be extracted for each light-emitting element, so that divisional coloring of RGB is unnecessary. Therefore, it is advantageous in realizing full-colorization for reasons such as ease of realization of high definition. In addition, since it becomes possible to enhance the light emission intensity in the front direction of a specific wavelength, it is possible to reduce power consumption. This configuration is particularly useful when applied to a color display (image display device) using pixels of three or more colors, but may be used for applications such as lighting.

(Embodiment 6)

In this embodiment, a light-emitting device having a light-emitting element in which the triarylamine compound, which is one embodiment of the present invention, is used in the light-emitting layer will be described.

Further, the light emitting device may be a passive matrix type light emitting device or an active matrix type light emitting device. In addition, it is possible to apply the light-emitting elements described in other embodiments to the light-emitting device according to the present embodiment.

In this embodiment, an active matrix type light emitting device will be described with reference to Figs. 5A and 5B.

In addition, FIG. 5A is a top view showing a light emitting device, and FIG. 5B is a cross-sectional view taken along a chain line A-A' in FIG. 5A. The active matrix type light emitting device according to the present embodiment includes a pixel portion 502 formed on an element substrate 501, a driving circuit portion (source line driving circuit) 503, and a driving circuit portion (gate line driving circuit) 504a. , 504b). The pixel portion 502, the driving circuit portion 503, and the driving circuit portions 504a and 504b are sealed between the element substrate 501 and the sealing substrate 506 by a sealing material 505.

Further, on the element substrate 501, external signals (for example, a video signal, a clock signal, a start signal, a reset signal, etc.) or a potential are applied to the driving circuit unit 503 and the driving circuit units 504a and 504b. Lead wiring 507 is formed to connect the transmitting external input terminal. Here, an example of forming an FPC (Flexible Print Circuit) 508 as an external input terminal is shown. In addition, although only the FPC is shown here, the printed wiring board (PWB) may be attached to this FPC. It is assumed that the light emitting device in the present specification includes not only the light emitting device main body but also a state in which the FPC or PWB is attached thereto.

Next, the cross-sectional structure will be described with reference to Fig. 5B. On the element substrate 501, a driving circuit portion and a pixel portion are formed. Here, a driving circuit portion 503 and a pixel portion 502, which are source line driving circuits, are shown.

The driving circuit section 503 shows an example in which a CMOS circuit in which an n-channel type TFT 509 and a p-channel type TFT 510 are combined is formed. Further, the circuit forming the driving circuit portion may be formed of various CMOS circuits, PMOS circuits, or NMOS circuits. Further, in the present embodiment, a driver integrated type in which a driving circuit is formed on a substrate is shown, but it is not necessary to do so, and a driving circuit may be formed outside the substrate instead of on the substrate.

Further, the pixel portion 502 includes a switching TFT 511, a first electrode (anode) electrically connected to the wiring (source electrode or drain electrode) of the current control TFT 512 and the current control TFT 512 ( It is formed by a plurality of pixels including 513. Further, an insulator 514 is formed covering the end of the first electrode (anode) 513. Here, it is formed by using a positive photosensitive acrylic resin.

Further, in order to provide good coverage of the film laminated on the upper layer, it is preferable that a curved surface having a curvature is formed at the upper end or the lower end of the insulating material 514. For example, when a positive photosensitive acrylic resin is used as the material of the insulating material 514, it is preferable to have a curved surface having a radius of curvature (0.2 μm to 3 μm) at the upper end of the insulating material 514. In addition, as the insulating material 514, either a negative type that is insoluble in the etchant by photosensitive light or a positive type that is soluble in the etchant by light can be used, and not limited to organic compounds. Both inorganic compounds such as silicon oxide and silicon oxynitride can be used.

On the first electrode (anode) 513, an EL layer 515 and a second electrode (cathode) 516 are stacked and formed. In the EL layer 515, at least a light emitting layer is formed. Further, in the EL layer 515, in addition to the light emitting layer, a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a charge generation layer, and the like can be appropriately formed. Further, the triarylamine compound as one embodiment of the present invention can be applied to a light emitting layer, a hole injection layer, a hole transport layer, or an electron transport layer.

Further, a light emitting element 517 is formed in a stacked structure of the first electrode (anode) 513, the EL layer 515, and the second electrode (cathode) 516. As the material used for the first electrode (anode) 513, the EL layer 515, and the second electrode (cathode) 516, the material shown in the second embodiment can be used. In addition, although not shown here, the 2nd electrode (cathode) 516 is electrically connected to the FPC 508 which is an external input terminal.

In addition, although only one light-emitting element 517 is shown in the cross-sectional view shown in FIG. 5B, it is assumed that in the pixel portion 502, a plurality of light-emitting elements are arranged in a matrix. In the pixel portion 502, light-emitting elements each of which light emission of three types (R, G, B) is obtained are selectively formed, and a light-emitting device capable of full-color display can be formed. Further, by combining with a color filter, a light emitting device capable of full color display may be obtained.

Further, by bonding the sealing substrate 506 with the element substrate 501 with the sealing material 505, the light emitting element 517 is placed in the space 518 surrounded by the element substrate 501, the sealing substrate 506, and the sealing material 505. ) Is provided. In addition, it is assumed that the space 518 is filled with an inert gas (nitrogen, argon, etc.), as well as a configuration filled with the sealing material 505.

In addition, it is preferable to use an epoxy resin for the sealing material 505. In addition, it is preferable that such a material is a material that does not permeate moisture or oxygen as much as possible. In addition, as a material used for the encapsulation substrate 506, in addition to a glass substrate or a quartz substrate, a plastic substrate made of fiberglass-reinforced plastics (FRP), polyvinyl fluoride (PVF), polyester, or acrylic may be used.

As described above, an active matrix type light emitting device can be obtained.

In addition, the configuration shown in this embodiment can be used in appropriate combinations of the configurations shown in the other embodiments.

(Embodiment 7)

In this embodiment, examples of various electronic devices completed using a light emitting device manufactured by applying a light emitting device containing a triarylamine compound, which is one embodiment of the present invention, will be described with reference to FIGS. 6A to 6D. .

As electronic devices to which a light emitting device is applied, for example, a television device (also referred to as a television or television receiver), a monitor for a computer, a digital camera, a digital video camera, a digital photo frame, and a mobile phone (cell phone, mobile phone device) Also referred to as), portable game machines, portable information terminals, sound reproduction devices, and large game machines such as pachinko machines. Specific examples of these electronic devices are shown in Figs. 6A to 6D.

6A shows an example of a television device. In the television device 7100, a display portion 7103 is incorporated in a housing 7101. An image can be displayed by the display portion 7103, and a light emitting device can be used for the display portion 7103. In addition, a configuration in which the housing 7101 is supported by a stand 7105 is shown here.

The television apparatus 7100 can be operated by an operation switch provided in the housing 7101 or a separate remote controller 7110. With the operation keys 7109 provided in the remote controller 7110, it is possible to manipulate a channel or a volume, and to manipulate an image displayed on the display portion 7103. Further, the remote controller 7110 may have a configuration in which a display portion 7107 that displays information output from the remote controller 7110 is provided.

In addition, the television device 7100 has a configuration including a receiver, a modem, and the like. General television broadcasting can be received by the receiver, and by connecting to a wired or wireless communication network via a modem, one-way (sender-to-recipient) or two-way (sender-to-recipient, or between-recipients, etc.) It is also possible to perform information communication.

6B is a computer, and includes a main body 7201, a housing 7202, a display portion 7203, a keyboard 7204, an external connection port 7205, a pointing device 7206, and the like. Further, a computer is manufactured by using a light emitting device for its display portion 7203.

6C is a portable game machine, which is composed of two housings, a housing 7301 and a housing 7302, and is connected to be openable and closed by a connection part 7303. The display part 7305 is built in the housing 7301 and the display part 7305 is built in the housing 7302. In addition, the portable game machine shown in Fig. 6C includes, in addition, a speaker unit 7306, a recording medium insertion unit 7307, an LED lamp 7308, an input means (operation key 7309, a connection terminal 7310), and a sensor ( 7311) (force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical, negative, time, hardness, electric field, current, voltage, power, radiation, Including a function of measuring flow rate, humidity, hardness, vibration, smell, or infrared light), a microphone 7312, etc. Of course, the configuration of the portable game machine is not limited to the above, and at least the display unit It is sufficient if a light emitting device is used for both or one of the display portion 7305 and the display portion 7305, and other accessory equipment can be suitably formed. The portable game machine shown in Fig. 6C has a program recorded on a recording medium. Alternatively, it has a function of reading data and displaying it on the display unit, or a function of sharing information by performing wireless communication with another portable game device, and the functions of the portable game device shown in Fig. 6C are not limited thereto, and various functions. Can have.

6D shows an example of a mobile phone. In addition to the display portion 7402 built in the housing 7401, the mobile phone 7400 includes an operation button 7403, an external connection port 7404, a speaker 7405, a microphone 7406, and the like. Further, the mobile phone 7400 is manufactured by using a light emitting device for the display portion 7402.

The mobile phone 7400 shown in FIG. 6D can input information by touching the display portion 7402 with a finger or the like. In addition, operations such as making a phone call or creating an e-mail can be performed by touching the display portion 7402 with a finger or the like.

The screen of the display unit 7402 mainly has three modes. The first is a display mode mainly for displaying an image, and the second is an input mode mainly for inputting information such as characters. The third is a display + input mode in which two modes of a display mode and an input mode are mixed.

For example, in the case of making a phone call or creating an e-mail, the display portion 7402 may be set to a character input mode mainly for inputting characters, and an operation for inputting characters displayed on the screen may be performed. In this case, it is preferable to display a keyboard or a number button on most of the screen of the display unit 7402.

In addition, by forming a detection device having a sensor that detects the inclination of a gyroscope, an acceleration sensor, etc. inside the mobile phone 7400, the orientation of the mobile phone 7400 (whether it is vertical or horizontal) is determined, The screen display on the display unit 7402 may be automatically switched.

In addition, switching of the screen mode is performed by touching the display portion 7402 or operating the operation button 7403 of the housing 7401. In addition, it is possible to switch according to the type of image displayed on the display unit 7402. For example, if the image signal to be displayed on the display unit is data of a moving picture, the display mode is switched, and if it is text data, the input mode is switched.

In addition, in the input mode, a signal detected by the optical sensor of the display unit 7402 is detected, and when there is no input by a touch operation of the display unit 7402 for a certain period, the mode of the screen is switched from the input mode to the display mode. You may control it to do so.

The display portion 7402 can also function as an image sensor. For example, by touching the display portion 7402 with a palm or a finger and taking an image of a palm print, a fingerprint, or the like, personal authentication can be performed. In addition, if a backlight emitting near-infrared light or a sensing light source emitting near-infrared light is used on the display unit, a finger vein, palm vein, or the like can be imaged.

In the manner described above, an electronic device can be obtained by applying the light emitting device of one embodiment of the present invention. The application range of the light emitting device is very wide, and it can be applied to electronic devices in all fields.

In addition, the configuration shown in this embodiment can be used in appropriate combination with the configuration shown in the other embodiments.

(Embodiment 8)

In this embodiment, an example of a lighting device completed using a light-emitting device manufactured by applying a light-emitting element containing a triarylamine compound, which is one embodiment of the present invention, will be described with reference to FIG. 7.

7 is an example in which the light emitting device is used as the indoor lighting device 8001. Further, since the light emitting device can also be made into a large area, a lighting device having a large area can also be formed. In addition, by using a housing having a curved surface, the lighting device 8002 in which the light emitting region has a curved surface may be formed. The light-emitting element included in the light-emitting device according to the present embodiment is in the form of a thin film and has a high degree of freedom in designing the housing. Therefore, it is possible to form a lighting device to which various designs were added. Further, a large-sized lighting device 8003 may be provided on an indoor wall surface.

Further, by using the light emitting device on the surface of the table, it is possible to obtain a lighting device 8004 having a function as a table. Further, by using a light emitting device for a part of other furniture, it is possible to obtain a lighting device having a function as a furniture.

As described above, various lighting devices to which a light emitting device is applied are obtained. In addition, these lighting devices are assumed to be included in one embodiment of the present invention.

In addition, the configuration shown in this embodiment can be used in appropriate combination with the configuration shown in the other embodiments.

[Example 1]

<< Synthesis Example 1 >>

In this example, a triarylamine compound, 4-phenyl-4'-(1-phenyl-1H-benzimidazol-2-yl)-, which is an embodiment of the present invention represented by the structural formula (100) of Embodiment 1 A method for synthesizing phenyl-triphenylamine (abbreviation: BPABIm) will be described. In addition, the structure of BPABIm (abbreviation) is shown below.

(100)

<Synthesis of 4-phenyl-4'-(1-phenyl-1H-benzimidazol-2-yl)-phenyl-triphenylamine (abbreviation: BPABIm)>

In a 100 mL 3-neck flask, 1.7 g (5.0 mmol) of 2-(4-bromophenyl)-1-phenyl-1H-benzimidazole, 1.2 g (5.0 mmol) of phenylbiphenylamine, sodium tert-butoxide 1.0 g (10 mmol) and 17 mg (30 μmol) of bis(dibenzylideneacetone)palladium (0) were added, and the atmosphere in the flask was replaced with nitrogen. To this mixture, 10 mL of dehydrated xylene was added. After degassing the mixture while stirring under reduced pressure, 200 mL (0.1 mmol) of tri(tert-butyl)phosphine (10 wt% hexane solution) was added. The mixture was heated and stirred at 130° C. for 5 hours in a nitrogen atmosphere, and reacted.

After the reaction, 200 mL of ethyl acetate was added to the reaction mixture, and the suspension was filtered through Florisil and Celite. The obtained filtrate was concentrated and purified by silica gel column chromatography (developing solvent toluene:ethyl acetate = 9:1). The obtained fraction was concentrated, acetone and methanol were added, ultrasonic waves were applied, and then recrystallized. As a result, a pale yellow powder as the target product was obtained in a yield of 2.1 g and a yield of 82%.

In addition, the reaction scheme of the above synthesis method is shown in Scheme A-1 below.

Scheme A-1

The analysis results of the compound obtained by the above synthesis by nuclear magnetic resonance spectroscopy ( ¹ H-NMR) are shown below. In addition, ¹ H-NMR chart is shown in Figs. 8A and 8B. Fig. 8B is an enlarged view of the range of 6 ppm to 9 ppm in Fig. 8A. From this result, 4-phenyl-4'-(1-phenyl-1H-benzimidazol-2-yl)-phenyl-tri, which is a triarylamine compound of one embodiment of the present invention represented by the above structural formula (100) It was found that phenylamine (abbreviation: BPABIm) was obtained.

Next, the ultraviolet visible absorption spectrum (hereinafter simply referred to as "absorption spectrum") and emission spectrum of BPABIm (abbreviation) were measured. For the measurement of the absorption spectrum, an ultraviolet-visible spectrophotometer (type V550 manufactured by Nippon Bunko Co., Ltd.) was used. In addition, for the measurement of the emission spectrum, a fluorescence photometer (FS920 manufactured by Hamamatsu Photonics Co., Ltd.) was used. In both the absorption spectrum and the emission spectrum, a toluene solution of BPABIm (abbreviation) and a thin film of BPABIm (abbreviation) were measured. In addition, in the case of a toluene solution (0.120 mmol/L), it was put into a quartz cell, and measurement was performed at room temperature. In the case of a thin film, a thin film deposited on a quartz substrate is used, and when measuring an absorption spectrum, a value obtained by subtracting the absorption spectrum of quartz from the absorption spectrum of the thin film is shown.

The measurement results of the obtained absorption spectrum and emission spectrum are shown in Figs. 9A and 9B. In addition, in FIG. 9A, the measurement result of the toluene solution of BPABIm (abbreviation) is shown. In addition, in FIG. 9B, the measurement result about the thin film of BPABIm (abbreviation) is shown. 9A and 9B, the horizontal axis represents wavelength (nm), and the vertical axis represents absorption intensity (arbitrary unit) or light emission intensity (arbitrary unit). In addition, although two solid lines are shown in Figs. 9A and 9B, a thin solid line represents an absorption spectrum, and a thick solid line represents an emission spectrum.

In the toluene solution of BPABIm (abbreviation) shown in Fig. 9A, an absorption peak appears around 361 nm, and in the thin film of BPABIm (abbreviation) shown in Fig. 9B, an absorption peak appears around 364 nm.

In addition, in the BPABIm (abbreviated) toluene solution shown in FIG. 9A, the maximum emission wavelength is 410 nm (excitation wavelength 365 nm), and in the BPABIm (abbreviated name) thin film shown in FIG. Was.

From the above, it was found that BPABIm (abbreviation) exhibits blue light emission with good color purity. Therefore, it can be used as a blue light emitting material.

In addition, the HOMO level and LUMO level of BPABIm (abbreviation) were determined by performing cyclic voltammetry (CV) measurement. For CV measurement, an electrochemical analyzer (manufactured by B·A·S Co., Ltd., model number: ALS model 600A or 600C) was used.

In addition, the solution in the CV measurement uses dehydrated dimethylformamide (DMF) (manufactured by Aldrich Co., Ltd., 99.8%, catalog number: 22705-6) as a solvent, and tetra-n-butylammonium perchlorate as a supporting electrolyte. (n-Bu ₄ NClO ₄ ) (Tokyo Kasei Co., Ltd. catalog number; T0836) was dissolved to a concentration of 100 mmol/L, and the measurement object was dissolved to a concentration of 2 mmol/L, and prepared. In addition, a platinum electrode (manufactured by B·A·S Co., Ltd., PTE platinum electrode) as a working electrode, and a platinum electrode (manufactured by B·A·S Co., Ltd., Pt counter electrode (5 cm) for VC-3) as an auxiliary electrode ), as a reference electrode, an Ag/Ag ⁺ electrode (manufactured by B·A·S Co., Ltd., RE7 non-aqueous solvent type reference electrode) was used, respectively. In addition, the measurement was performed at room temperature (20 to 25°C), and the scanning speed at the time of measurement was unified at 0.1 V/sec. In addition, in this example, the potential energy of the reference electrode with respect to the vacuum level is assumed to be -4.94 eV.

Since the intermediate potential (half wave potential) between the oxidation peak potential (E _pa ) and the reduction peak potential (E _pc ) obtained in CV measurement corresponds to the HOMO level, the HOMO level of BPABIm (abbreviation) is calculated as -5.37 eV. , In addition, the LUMO level of BPABIm (abbreviation) was calculated as -2.28 eV. Therefore, it was found that the band gap (ΔE) of BPABIm (abbreviation) was 3.09 eV.

Therefore, it was found that BPABIm (abbreviation) has a wide band gap.

Moreover, even after 100 cycles, the oxidation peak became the same value. It was found that it exhibits good properties in repetition of redox between an oxidized state and a neutral state.

Therefore, it was found that BPABIm (abbreviation) transports holes well.

[Example 2]

<< Synthesis Example 2 >>

In this example, the triarylamine compound, which is one embodiment of the present invention represented by the structural formula (135) of the first embodiment, N,N'-diphenyl-N,N'-di-{4-(1,3- A method for synthesizing benzoxazol-2-yl)-phenyl}benzidine (abbreviation: BOxABP) will be described. In addition, the structure of BOxABP (abbreviation) is shown below.

(135)

<Synthesis of N,N'-diphenyl-N,N'-di-{4-(1,3-benzoxazol-2-yl)-phenyl}benzidine (abbreviation: BOxABP)>

In a 50 mL 3-neck flask, 1.4 g (5.2 mmol) of 2-(4-bromophenyl)-1,3-benzoxazole, 0.8 g (2.5 mmol) of N,N'-diphenylbenzidine, sodium tert- 1.0 g (10 mmol) of butoxide and 28 mg (50 µol) of bis(dibenzylideneacetone)palladium (0) were added, and the atmosphere in the flask was replaced with nitrogen. To this mixture, 20 mL of dehydrated xylene was added. After degassing the mixture while stirring under reduced pressure, 0.3 mL (0.2 mmol) of tri(tert-butyl)phosphine (10 wt% hexane solution) was added. This mixture was heated and stirred at 130° C. for 4.5 hours in a nitrogen atmosphere, and reacted.

After the reaction, 200 mL of ethyl acetate was added to the reaction mixture, and the suspension was filtered through Florisil and Celite. The obtained filtrate was concentrated and purified by silica gel column chromatography (developing solvent toluene:ethyl acetate = 9:1). The obtained fraction was concentrated, acetone and methanol were added, ultrasonic waves were applied, and then recrystallized to obtain a target product, yellow powder, in a yield of 1.7 g and a yield of 96%.

In addition, the reaction scheme of the above synthesis method is shown in Scheme B-1 below.

Scheme B-1

The Rf value (developing solvent, ethyl acetate:hexane = 1:5) in silica gel thin layer chromatography (TLC) was 0.35 for the target product, and 0.67 for 2-(4-bromophenyl)-1,3-benzoxazole. , N,N'-diphenylbenzidine was 0.30.

The analysis results of the compound obtained by the above synthesis by nuclear magnetic resonance spectroscopy ( ¹ H-NMR) are shown below. In addition, ¹ H-NMR chart is shown in Figs. 10A and 10B. Fig. 10B is an enlarged view of the range of 6 ppm to 9 ppm in Fig. 10A. From this result, N,N'-diphenyl-N,N'-di-{4-(1,3-benzoxazole, which is a triarylamine compound of one embodiment of the present invention represented by the above structural formula (135) It was found that -2-yl)-phenyl}benzidine (abbreviation: BOxABP) was obtained.

Next, the ultraviolet and visible absorption spectrum (hereinafter simply referred to as "absorption spectrum") and emission spectrum of BOxABP (abbreviation) were measured. For the measurement of the absorption spectrum, an ultraviolet-visible spectrophotometer (type V550 manufactured by Nippon Bunko Co., Ltd.) was used. In addition, for the measurement of the emission spectrum, a fluorescence photometer (FS920 manufactured by Hamamatsu Photonics Co., Ltd.) was used. In both the absorption spectrum and the emission spectrum, a toluene solution of BOxABP (abbreviation) and a thin film of BOxABP (abbreviation) were measured. In addition, in the case of a toluene solution (0.120 mmol/L), it was put into a quartz cell, and measurement was performed at room temperature. In the case of a thin film, a thin film deposited on a quartz substrate is used, and in the case of measuring an absorption spectrum, a value obtained by subtracting the absorption spectrum of quartz from the absorption spectrum of the thin film is shown.

The measurement results of the obtained absorption spectrum and emission spectrum are shown in Figs. 11A and 11B. In addition, in FIG. 11A, the measurement result of the toluene solution of BOxABP (abbreviation) is shown. In addition, in FIG. 11B, the measurement result of the thin film of BOxABP (abbreviation) is shown. 11A and 11B, the horizontal axis represents wavelength (nm), and the vertical axis represents absorption intensity (arbitrary unit) or light emission intensity (arbitrary unit). In addition, in Figs. 11A and 11B, two solid lines are shown, but a thin solid line indicates an absorption spectrum, and a thick solid line indicates an emission spectrum.

In the toluene solution of BOxABP (abbreviation) shown in Fig. 11A, an absorption peak appears around 381 nm, and in the thin film of BOxABP (abbreviation) shown in Fig. 11B, an absorption peak appears around 384 nm.

In addition, in the BOxABP (abbreviated) toluene solution shown in FIG. 11A, the maximum emission wavelength is 435 nm (excitation wavelength 380 nm), and in the BOxABP (abbreviated name) thin film shown in FIG. Was.

From the above, it was found that BOxABP (abbreviation) exhibits blue light emission. Therefore, it can be used as a blue light emitting material.

In addition, the HOMO level and LUMO level of BOxABP (abbreviation) were determined by performing cyclic voltammetry (CV) measurement. For CV measurement, an electrochemical analyzer (manufactured by B·A·S Co., Ltd., model number: ALS model 600A or 600C) was used.

In addition, the solution in the CV measurement uses dehydrated dimethylformamide (DMF) (manufactured by Aldrich Co., Ltd., 99.8%, catalog number: 22705-6) as a solvent, and tetra-n-butyl perchlorate as a supporting electrolyte. Ammonium (n-Bu ₄ NClO ₄ ) (Tokyo Kasei Co., Ltd. catalog number; T0836) was dissolved to a concentration of 100 mmol/L, and the measurement object was dissolved to a concentration of 2 mmol/L to prepare. In addition, a platinum electrode (manufactured by B·A·S Co., Ltd., PTE platinum electrode) as a working electrode, and a platinum electrode (manufactured by B·A·S Co., Ltd., Pt counter electrode (5 cm) for VC-3) as an auxiliary electrode ), as a reference electrode, an Ag/Ag ⁺ electrode (manufactured by B·A·S Co., Ltd., RE7 nonaqueous solvent type reference electrode) was used, respectively. In addition, the measurement was performed at room temperature (20 to 25°C), and the scanning speed at the time of measurement was unified at 0.1 V/sec. In addition, in this example, the potential energy of the reference electrode with respect to the vacuum level was set to -4.94 eV.

Since the intermediate potential (half wave potential) between the oxidation peak potential (E _pa ) and the reduction peak potential (E _pc ) obtained by CV measurement corresponds to the HOMO level, the HOMO level of BOxABP (abbreviation) is calculated as -5.50 eV. , In addition, the LUMO level of BOxABP (abbreviation) was calculated as -2.59 eV. Therefore, it was found that the band gap (ΔE) of BOxABP (abbreviation) was 2.91 eV.

Therefore, it was found that BOxABP (abbreviation) has a wide band gap.

Moreover, even after 100 cycles, the oxidation peak became the same value. It was found that it exhibits good properties in repetition of redox between an oxidized state and a neutral state.

Therefore, it was found that BOxABP (abbreviation) transports holes well.

[Example 3]

In this example, the triarylamine compound of the present invention, 4-phenyl-4'-(1-phenyl-1H-benzimidazol-2-yl)-phenyl-triphenylamine (abbreviation: BPABIm) (structural formula (100 Light-emitting element 1 in which )) is used for the hole transport layer will be described with reference to FIG. 12. In addition, the chemical formula of the material used in this example is shown below.

<< Fabrication of Light-Emitting Element 1 >>

First, indium tin oxide (ITSO) containing silicon oxide was formed on a glass substrate 1100 by a sputtering method, and a first electrode 1101 serving as an anode was formed. In addition, the film thickness was set to 110 nm, and the electrode area was set to 2 mm×2 mm.

Next, as a pretreatment for forming a light emitting element on the substrate 1100, the surface of the substrate was washed with water, fired at 200°C for 1 hour, and then UV ozone treatment was performed for 370 seconds.

Thereafter, the ^{substrate was introduced into a vacuum evaporation apparatus whose interior was decompressed to about 10 -4} Pa, and vacuum firing was performed at 170°C for 30 minutes in a heating chamber in the vacuum evaporation apparatus, and then the substrate 1100 was subjected to 30 minutes. It was cool enough.

Next, the substrate 1100 was fixed to a holder formed in a vacuum evaporation apparatus so that the surface on which the first electrode 1101 was formed became downward. In this embodiment, a hole injection layer 1111 constituting the EL layer 1102, a hole transport layer 1112, a light emitting layer 1113, an electron transport layer 1114, and an electron injection layer 1115 constituting the EL layer 1102 are sequentially formed by vacuum evaporation. The case where it is formed will be described.

After reducing the pressure in the vacuum apparatus to 10 ^-4 Pa, 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) and molybdenum oxide (VI) were added to BPAFLP (abbreviation). ): molybdenum oxide = 4:2 (mass ratio) by co-depositing to form a hole injection layer 1111 on the first electrode 1101. The film thickness was set to 50 nm. In addition, co-deposition is a vapor deposition method in which a plurality of different substances are simultaneously evaporated from different evaporation sources, respectively.

Next, the hole transport layer 1112 was formed by depositing 10 nm of 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP).

Next, a light emitting layer 1113 was formed on the hole transport layer 1112. First of all, 2-[4-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole ((abbreviation: DBTBIm-II), 4-phenyl-4'-(1-phenyl- 1H-benzimidazol-2-yl)-phenyl-triphenylamine (abbreviation: BPABIm), tris (2-phenylpyridinato-N,C ^2' ) iridium (abbreviation: Ir (ppy) ₃ ), DBTBIm -II (abbreviation):BPABIm (abbreviation):Ir(ppy) ₃ (abbreviation) = 1:0.5:0.06 (mass ratio) In addition, the film thickness was set to 20 nm Next, DBTBIm-II (Abbreviation) and Ir(ppy) ₃ (abbreviation) were co-deposited so that DBTBIm-II (abbreviated name):Ir(ppy) ₃ (abbreviated name) = 1:0.06 (mass ratio), and the film thickness was set to 20 nm. Thus, the light emitting layer 1113 having a laminated structure was formed.

Next, an electron transport layer 1114 was formed by depositing 20 nm of tris(8-quinolinolato)aluminum(III) (abbreviation: Alq) on the light emitting layer 1113. In addition, 10 nm of vasophenanthroline (abbreviation: Bphen) was deposited on the electron transport layer 1114 and then 1 nm of lithium fluoride was further deposited to form the electron injection layer 1115.

Finally, aluminum was vapor-deposited on the electron injection layer 1115 so as to have a film thickness of 200 nm, and a second electrode 1103 serving as a cathode was formed, and light-emitting element 1 was obtained. In addition, in the above deposition process, all deposition was performed using a resistance heating method.

Table 1 shows the device structure of Light-Emitting Element 1 thus obtained.

Further, the produced light-emitting element 1 was sealed in a glove box in a nitrogen atmosphere so as not to be exposed to the atmosphere (a sealant was applied around the element and heat-treated at 80° C. for 1 hour at the time of sealing).

《Operation Characteristics of Light-Emitting Element 1》

The operation characteristics of the produced light-emitting element 1 were measured. In addition, the measurement was performed at room temperature (atmosphere maintained at 25°C).

First, the current density-luminance characteristics of Light-Emitting Element 1 are shown in FIG. 13. In addition, voltage-luminance characteristics are shown in Fig. 14, luminance-current efficiency characteristics are shown in Fig. 15, voltage-current characteristics are shown in Fig. 16, and luminance-chromaticity characteristics are shown in Fig. 17, respectively.

13 to 15, it was found that the light-emitting element 1 in which the triarylamine compound of one embodiment of the present invention was used for the hole transport layer was a high-efficiency element with low power consumption. Further, from Fig. 16, it was found that the device has a low driving voltage. In addition, from Fig. 17, it was found that the device has a good carrier balance at each luminance.

In addition, the main initial characteristic values of the light-emitting element 1 in the vicinity of 1000 cd/m 2 are shown in Table 2 below.

From the results in Table 2, it can be seen that the light-emitting element 1 fabricated in this example has high luminance and high current efficiency. In addition, regarding color purity, it can be seen that green light emission with good purity is exhibited.

Further, the emission spectrum when a current is passed through the light-emitting element 1 at a current density of 25 mA/cm 2 is shown in FIG. 18. As shown in Fig. 18, it is suggested that the emission spectrum of Light-Emitting Element 1 has peaks around 514 nm and 545 nm, and originates from the light emission of _{Ir(ppy) 3 (abbreviated name) contained in the light-emitting layer 1113.}

Therefore, BPABIm (abbreviation) has a T1 level higher than that of a substance emitting green light, and can be used as a host material or a carrier transport material of an element that exhibits phosphorescence from green to long wavelengths.

In addition, a reliability test was conducted on Light-Emitting Element 1. Fig. 19 shows the results of the reliability test. In Fig. 19, the vertical axis represents the normalized luminance (%) when the initial luminance is 100%, and the horizontal axis represents the driving time (h) of the device. Further, in the reliability test, the initial luminance was set to 1000 cd/m 2, and the light-emitting element 1 was driven under constant current density conditions. From Fig. 19, the luminance of Light-Emitting Element 1 after 640 hours was maintained at 75% of the initial luminance. Accordingly, it was found that the light-emitting element 1 exhibits high reliability. In addition, it was found that by using the triarylamine compound of the present invention in a light emitting device, a light emitting device having a long life can be obtained.

[Example 4]

In this example, the triarylamine compound of the present invention, N,N'-diphenyl-N,N'-di-{4-(1,3-benzoxazol-2-yl)-phenyl}benzidine (abbreviation : BOxABP) (Structural Formula (135)) will be described with respect to the hole injection layer or the hole transport layer, and light-emitting elements 2 to 4 in which both are used. In addition, in the description of Light-Emitting Elements 2 to 4 in this embodiment, it is assumed that Fig. 12 used for the description of Light-Emitting Element 1 in Example 1 is used. In addition, the chemical formula of the material used in this example is shown below.

<< Fabrication of Light-Emitting Element 2 to Light-Emitting Element 4 >>

First, indium tin oxide (ITSO) containing silicon oxide was formed on a glass substrate 1100 by a sputtering method, and a first electrode 1101 serving as an anode was formed. In addition, the film thickness was set to 110 nm, and the electrode area was set to 2 mm×2 mm.

Next, as a pretreatment for forming a light emitting element on the substrate 1100, the surface of the substrate was washed with water, fired at 200°C for 1 hour, and then UV ozone treatment was performed for 370 seconds.

Thereafter, the ^{substrate was introduced into a vacuum evaporation apparatus whose interior was decompressed to about 10 -4} Pa, and vacuum firing was performed at 170°C for 30 minutes in a heating chamber in the vacuum evaporation apparatus, and then the substrate 1100 was subjected to 30 minutes. It was cool enough.

Next, the substrate 1100 was fixed to a holder formed in a vacuum evaporation apparatus so that the surface on which the first electrode 1101 was formed was positioned downward. In this embodiment, a hole injection layer 1111 constituting the EL layer 1102, a hole transport layer 1112, a light emitting layer 1113, an electron transport layer 1114, and an electron injection layer 1115 constituting the EL layer 1102 are sequentially formed by vacuum evaporation. The case where it is formed will be described.

After reducing the pressure in the vacuum device to 10 ^-4 Pa, in the case of light-emitting element 2, 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) and oxidation A hole injection layer 1111 was formed on the first electrode 1101 by co-depositing molybdenum (VI) so that NPB (abbreviation): molybdenum oxide = 4:1 (mass ratio). The film thickness was set to 50 nm. In the case of Light-Emitting Element 3 and Light-Emitting Element 4, BOxABP (abbreviation) and molybdenum oxide (VI) were co-deposited so that BOxABP (abbreviation): molybdenum oxide = 4: 1 (mass ratio), the first electrode 1101 ) To form a hole injection layer 1111 on it. The film thickness was set to 50 nm.

Next, in the case of Light-Emitting Elements 2 and 4, the hole transport layer 1112 was formed by depositing 10 nm of BOxABP (abbreviated name). In the case of Light-Emitting Element 3, the hole transport layer 1112 was formed by depositing 10 nm of NPB (abbreviated name).

Next, a light emitting layer 1113 was formed on the hole transport layer 1112. 9-[4-(N-carbazolyl)]phenyl-10-phenylanthracene (abbreviation: CzPA), 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9H-carbazole 3-yl)triphenylamine (abbreviation: PCBAPA) was co-deposited so that CzPA (abbreviation):PCBAPA (abbreviation) = 1:0.1 (mass ratio), and a light emitting layer 1113 was formed. The film thickness was set to 30 nm.

Next, an electron transport layer 1114 was formed by depositing 10 nm of tris(8-quinolinolato)aluminum(III) (abbreviation: Alq) on the light emitting layer 1113. In addition, 20 nm of vasophenanthroline (abbreviated: Bphen) was deposited on the electron transport layer 1114 and then 1 nm of lithium fluoride was deposited to form the electron injection layer 1115.

Finally, aluminum was deposited on the electron injection layer 1115 so as to have a film thickness of 200 nm, and a second electrode 1103 serving as a cathode was formed, and Light-Emitting Elements 2 to 4 were obtained. In addition, in the above deposition process, all deposition was performed using a resistance heating method.

Table 3 shows the device structures of Light-Emitting Elements 2 to 4 thus obtained.

In addition, the produced Light-Emitting Elements 2 to 4 were sealed in a glove box in a nitrogen atmosphere so as not to be exposed to the atmosphere (a sealant was applied around the element and heat-treated at 80° C. for 1 hour at the time of sealing).

<<Operation Characteristics of Light-Emitting Elements 2 to 4>>

The operation characteristics of the prepared Light-Emitting Elements 2 to 4 were measured. In addition, the measurement was performed at room temperature (atmosphere maintained at 25°C).

First, the current density-luminance characteristics of Light-Emitting Elements 2 to 4 are shown in FIG. 20. In addition, voltage-luminance characteristics are shown in Fig. 21, luminance-current efficiency characteristics are shown in Fig. 22, and voltage-current characteristics are shown in Fig. 23, respectively.

From Figs. 20 to 22, it was found that Light-Emitting Elements 2 to 4 using the triarylamine compound of one embodiment of the present invention are devices with low power consumption and high efficiency. In addition, from Fig. 23, it was found that the device has a low driving voltage.

In addition, the main initial characteristic values of Light-Emitting Elements 2 to 4 in the vicinity of 1000 cd/m 2 are shown in Table 4 below.

From the results of Table 4, it can be seen that the light-emitting elements 2 to 4 manufactured in this example have high luminance and high current efficiency.

In addition, light emission spectra when current is passed through Light-Emitting Elements 2 to 4 at a current density of 25 mA/cm 2 are shown in FIG. 24. As shown in Fig. 24, it was suggested that the emission spectra of Light-Emitting Elements 2 to 4 have a peak around 470 nm, and originate from the light emission of PCBAPA (abbreviation) contained in the light-emitting layer 1113.

Further, a reliability test was conducted on Light-Emitting Element 3. Further, in the reliability test, the initial luminance was set to 1000 cd/m 2, and the light-emitting element 3 was driven under constant current density conditions. As a result, the luminance of Light-Emitting Element 3 after 550 hours maintained 79% of the initial luminance. Accordingly, it was found that the light-emitting element 3 in which the triarylamine compound, which is one embodiment of the present embodiment, is used for the hole injection layer exhibits high reliability. In addition, it was found that by using the triarylamine compound of the present invention in a light emitting device, a light emitting device having a long life can be obtained.

[Example 5]

In this example, the triarylamine compound of the present invention, N,N'-diphenyl-N,N'-di-{4-(1,3-benzoxazol-2-yl)-phenyl}benzidine (abbreviation : BOxABP) (Structural Formula (135)) is used in the light-emitting layer The light-emitting element 5 will be described. In addition, for the description of the light-emitting element 5 in the present embodiment, Fig. 12 used for the description of the light-emitting element 1 in the first embodiment will be used. In addition, the chemical formula of the material used in this example is shown below.

<< fabrication of light-emitting element 5 >>

First, indium tin oxide (ITSO) containing silicon oxide was formed on a glass substrate 1100 by a sputtering method, and a first electrode 1101 serving as an anode was formed. In addition, the film thickness was set to 110 nm, and the electrode area was set to 2 mm×2 mm.

Next, as a pretreatment for forming a light emitting element on the substrate 1100, the surface of the substrate was washed with water, fired at 200°C for 1 hour, and then UV ozone treatment was performed for 370 seconds.

Thereafter, the ^{substrate was introduced into a vacuum evaporation apparatus whose interior was decompressed to about 10 -4} Pa, and vacuum firing was performed at 170°C for 30 minutes in a heating chamber in the vacuum evaporation apparatus, and then the substrate 1100 was subjected to 30 minutes. It was cool enough.

Next, the substrate 1100 was fixed to a holder formed in a vacuum evaporation apparatus so that the surface on which the first electrode 1101 was formed was positioned downward. In this embodiment, a hole injection layer 1111 constituting the EL layer 1102, a hole transport layer 1112, a light emitting layer 1113, an electron transport layer 1114, and an electron injection layer 1115 constituting the EL layer 1102 are sequentially formed by vacuum evaporation. The case where it is formed will be described.

After reducing the pressure in the vacuum device to 10 ^-4 Pa, 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) and molybdenum (VI) oxide were added to NPB. (Abbreviation): Molybdenum oxide = 4: 1 (mass ratio) by co-depositing to form a hole injection layer 1111 on the first electrode 1101. The film thickness was set to 50 nm.

Next, 10 nm of NPB (abbreviation) was deposited, and 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA ) Was deposited at 30 nm to form a hole transport layer 1112.

Next, a light emitting layer 1113 was formed on the hole transport layer 1112. 9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: CzPA), BOxABP (abbreviation), PCBAPA (abbreviation), CzPAA (abbreviation): BOxABP (abbreviation): PCBAPA It co-deposited so that (abbreviation) = 1:0.05:0.1 (mass ratio), and the light emitting layer 1113 was formed. The film thickness was set to 30 nm.

Next, an electron transport layer 1114 was formed by depositing 10 nm of tris(8-quinolinolato)aluminum(III) (abbreviation: Alq) on the light emitting layer 1113. Further, an electron injection layer 1115 was formed by depositing 1 nm of lithium fluoride on the electron transport layer 1114.

Finally, aluminum was vapor-deposited on the electron injection layer 1115 so as to have a film thickness of 200 nm, and a second electrode 1103 serving as a cathode was formed, thereby obtaining a light-emitting element 5. In addition, in the above deposition process, all deposition was performed using a resistance heating method.

Table 5 shows the device structure of Light-Emitting Element 5 thus obtained.

Further, the produced light-emitting element 5 was sealed in a glove box in a nitrogen atmosphere so as not to be exposed to the atmosphere (a sealant was applied around the element and heat-treated at 80° C. for 1 hour at the time of sealing).

《Operation Characteristics of Light-Emitting Element 5》

The operation characteristics of the produced light-emitting element 5 were measured. In addition, the measurement was performed at room temperature (atmosphere maintained at 25°C).

First, the current density-luminance characteristics of Light-Emitting Element 5 are shown in FIG. 25. In addition, voltage-luminance characteristics are shown in Fig. 26, luminance-current efficiency characteristics are shown in Fig. 27, and voltage-current characteristics are shown in Fig. 28, respectively.

26 and 27, it was found that the light-emitting element 5 in which the triarylamine compound of one embodiment of the present invention was used in the light-emitting layer was a high-efficiency element with low power consumption. Further, from Fig. 28, it was found that the device has a low driving voltage.

In addition, the main initial characteristic values of the light-emitting element 5 in the vicinity of 1000 cd/m 2 are shown in Table 6 below.

From the results of Table 6, it can be seen that the light-emitting element 5 fabricated in this example has high luminance and high current efficiency.

Further, the emission spectrum when a current is passed through the light-emitting element 5 at a current density of 25 mA/cm 2 is shown in FIG. 29. As shown in Fig. 29, it is suggested that the emission spectrum of Light-Emitting Element 5 has a peak around 473 nm, and originates from the light emission of BOxABP (abbreviation) contained in the light-emitting layer 1113.

Accordingly, it was found that BOxABP (abbreviation) has a higher S1 level than a substance emitting blue light, and can be used as a host material or a carrier transport material of an element that exhibits fluorescence from blue to long wavelength.

Further, a reliability test was performed on the light-emitting element 5. In the reliability test, the initial luminance was set to 1000 cd/m 2, and the light-emitting element 5 was driven under constant current density conditions. As a result, the luminance of Light-Emitting Element 5 after 450 hours maintained 79% of the initial luminance. Therefore, it was found that the light-emitting element 5 exhibits high reliability. In addition, it was found that the use of the triarylamine compound of the present invention in the hole injection layer of the light emitting device provides a light emitting device having a long life.

101 first electrode
102 EL layer
103 second electrode
111 hole injection layer
112 hole transport layer
113 Emitting Layer
114 electron transport layer
115 electron injection layer
116 charge generation layer
201 anode
202 cathode
203 EL layer
204 light emitting layer
205 phosphorescent compound
206 first organic compound
207 Second Organic Compound
301 first electrode
302(1) first EL layer
302(2) second EL layer
302(n-1)th (n-1) EL layer
302(n)th (n) EL layer
304 second electrode
305 charge generation layer (I)
305(1) first charge generation layer (I)
305(2) second charge generation layer (I)
305(n-2)th (n-2)th charge generation layer (I)
305(n-1)th (n-1)th charge generation layer (I)
401 reflective electrode
402 transflective/reflective electrode
403a first transparent conductive layer
403b second transparent conductive layer
404B first light-emitting layer (B)
404G second emission layer (G)
404R third light-emitting layer (R)
405 EL layer
410R first light-emitting element (R)
410G second light-emitting element (G)
410B third light-emitting element (B)
501 element board
502 pixel unit
503 driving circuit unit (source line driving circuit)
504a, 504b driving circuit unit (gate line driving circuit)
505 seal material
506 encapsulated substrate
507 wiring
508 FPC (Flexible Print Circuit)
509 n-channel TFT
510 p-channel TFT
511 switching TFT
512 TFT for current control
513 first electrode (anode)
514 insulation
515 EL layer
516 second electrode (cathode)
517 light-emitting element
518 space
1100 substrate
1101 first electrode
1102 EL layer
1103 second electrode
1111 hole injection layer
1112 hole transport layer
1113 emitting layer
1114 electron transport layer
1115 electron injection layer
7100 television device
7101 housing
7103 display
7105 stand
7107 display
7109 operation keys
7110 remote controller
7201 main unit
7202 housing
7203 display
7204 keyboard
7205 external connection port
7206 pointing device
7301 housing
7302 housing
7303 connection
7304 display
7305 display
7306 speaker unit
7307 recording medium insert
7308 LED lamp
7309 operation keys
7310 connection terminal
7311 sensor
7312 microphone
7400 mobile phone
7401 housing
7402 display
7403a, 7403b control buttons
7404 external connection port
7405 speaker
7406 microphone
8001 lighting device
8002 lighting device
8003 lighting device
8004 lighting device

Claims (8)

A compound represented by the following formula G1.
Formula G1

In Formula G1,
E ¹ is an oxygen atom;
α ¹ to α ³ are each independently a substituted or unsubstituted phenylene group or a substituted or unsubstituted biphenylene group;
m and n are each independently 0 or 1;
Ar ¹ is an aryl group represented by the following formula G1-2;
Ar ² is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted A substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group;
Each of R ¹ to R ⁴ independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group.
Formula G1-2

In Formula G1-2,
E ² is an oxygen atom;
α ⁴ to α ⁶ are each independently a substituted or unsubstituted phenylene group or a substituted or unsubstituted biphenylene group;
q is 0 or 1;
Ar ³ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted A substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group;
Each of R ⁵ to R ⁸ independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. A compound represented by the formula G2.
Formula G2

In Formula G2,
E ¹ is an oxygen atom;
α ¹ is a substituted or unsubstituted phenylene group or a substituted or unsubstituted biphenylene group;
m and n are each independently 0 or 1;
Ar ¹ is an aryl group represented by the following formula G2-2;
Ar ² is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted A substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group;
Each of R ¹ to R ⁴ independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group.
Formula G2-2

In Formula G2-2,
E ² is an oxygen atom;
α ⁴ is a substituted or unsubstituted phenylene group, or a substituted or unsubstituted biphenylene group;
q is 0 or 1;
Ar ³ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted A substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group;
Each of R ⁵ to R ⁸ independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. A compound represented by the formula G3.
Formula G3

In Formula G3,
E ¹ is an oxygen atom;
m and n are each independently 0 or 1;
Ar ¹ is an aryl group represented by the following formula G3-2;
Ar ² is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted A substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group;
Each of R ¹ to R ⁴ independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group.
Formula G3-2

In Formula G3-2,
E ² is an oxygen atom;
q is 0 or 1;
Ar ³ is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted A substituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted dibenzofuranyl group;
Each of R ⁵ to R ⁸ independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. A compound represented by structural formula (135).

A light-emitting device comprising the compound according to any one of claims 1 to 4. A light-emitting device comprising the light-emitting element according to claim 5. An electronic device comprising the light emitting device according to claim 6. A lighting device comprising the light emitting device according to claim 6.

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